1. Controllability of conditions and behavior of the subject. When conducting an experiment, it is necessary to take into account all the features of the situation and the capabilities of the animal. This is not always easy to do, since animals, unlike humans, cannot be given instructions and rely on their conscious execution. Therefore, the experimental situation should be designed in such a way as to minimize unexpected reactions of the animals. In all cases, such reactions are recorded in the observation protocol and are used to interpret the data obtained. In animal psychology, there are often cases when an animal, especially one with a highly developed psyche, reacts to an experimental situation differently than the researcher expected. For example, in W. Koehler's experiments, chimpanzees were asked to reach a high-hanging bait using a stick, which the researcher assumed the monkey would hold in his hand. However, in some cases, the chimpanzees used the stick as a jumping pole or quickly climbed onto it, placing it vertically under the bait. It turned out that it is sometimes more difficult for a monkey to manipulate a long stick while standing than to use it as a device for locomotion. In experiments using a stick to roll bait out of a simple maze (W. Köhler, E.G. Vatsuro, G.G. Filippova), chimpanzees and orangutans consistently used a number of methods not taken into account by scientists, which had to be consistently eliminated in order to test the hypothesis. The monkeys, instead of rolling the bait along the passages of the maze with a stick, threw the bait over the side of the maze, prying it up with a stick, dragged it, pressing it against the side with a stick, and even accurately hit the experimental table from below, as a result of which the bait jumped up and fell over the side of the maze . Orangutans behaved in a similar way when they were asked to push the bait out of the tube with a stick (G.G. Filippova). They shook out the bait, knocking the tube on the floor, and even blew it out with their mouth, rolled out and kneaded the tube on the floor, etc. Thus, the very process of the animal’s activity changed: it had to not get the bait in the only possible way, following from the situation itself, but find the method that was permitted and reinforced by the experimenter. Research by almost all scientists who have studied and are studying the psyche of higher animals, and especially monkeys, indicates that in a number of cases we are dealing with precisely such a situation, i.e. we are studying not the animal’s ability to act in the proposed objective situation, but its ability to identify problem posed by a person and find an appropriate solution. Therefore, the requirement to control the experimental conditions and the behavior of the animal is one of the most important and at the same time difficult to implement principles of conducting an experiment.

2. Availability of a specially developed procedure for conducting an experiment and recording the data obtained. This principle reflects the essence of the experimental method. For each experiment, a procedure is specially developed, which includes the sequence of all events and actions of the experimenter and the subject, a description of the recorded forms of animal behavior and the method of such recording. The received data is processed in a specially developed way. This allows you to compare data obtained in different series of experiments and by different researchers, which ensures their reliability and objectivity.

3. The possibility of repeating the experiment with the same and other animals, as well as other researchers. When conducting an experiment and presenting the data obtained, it is mandatory to present the methodology and results in such a form that they can be assessed and, if necessary, repeated by other researchers. This is what allows us to ultimately understand the causes and mechanisms of animal behavior. Often, researchers using the same technique obtain different results, the comparison of which makes it possible to identify the true characteristics of the psyche of the animals being studied.

4. Objectivity. This principle involves accurate recording and unbiased interpretation of animal behavior, regardless of whether it corresponds to the researcher’s hypothesis. Animal psychology, like any science in general, unfortunately, is not free from either the ideological or personal characteristics of the researcher. Therefore, objective recording of data, a detailed presentation of the methodology, the availability and safety of observation and experimental protocols are mandatory and necessary in zoopsychological research.

V.V. Nikandrov points out that achieving the main goal of the experiment - the utmost possible unambiguity in understanding the connections between the phenomena of internal mental life and their external manifestations - is achieved thanks to the following main characteristics of the experiment:

1) the initiative of the experimenter in the manifestation of psychological facts of interest to him;

2) the possibility of varying the conditions for the emergence and development of mental phenomena;

3) strict control and recording of conditions and the process of their occurrence;

4) isolating some and emphasizing other factors that determine the phenomena being studied, which makes it possible to identify the patterns of their existence;

5) the possibility of repeating experimental conditions for multiple verification of the obtained scientific data and their accumulation;

6) varying the conditions for quantitative assessments of the identified patterns.

Thus, a psychological experiment can be defined as a method in which the researcher himself causes the phenomena of interest to him and changes the conditions for their occurrence in order to establish the reasons for the occurrence of these phenomena and the patterns of their development. In addition, the obtained scientific facts can be repeatedly reproduced due to controllability and strict control of conditions, which makes it possible to verify them, as well as the accumulation of quantitative data, on the basis of which one can judge the typicality or randomness of the phenomena being studied.

There are several types of experiments. Depending on the way of organizing There are laboratory, natural and field experiments. Laboratory the experiment is carried out under special conditions. The researcher plans and purposefully influences the object of study in order to change its state. The advantage of a laboratory experiment can be considered strict control over all conditions, as well as the use of special equipment for measurement. The disadvantage of a laboratory experiment is the difficulty of transferring the obtained data to real conditions. The subject in a laboratory experiment is always aware of his participation in it, which can cause motivational distortions.

Natural The experiment is carried out under real conditions. Its advantage is that the study of an object is carried out in the context of everyday life, so the data obtained are easily transferred to reality. The subjects are not always informed about their participation in the experiment, so they do not give motivational distortions. Disadvantages: inability to control all conditions, unexpected interference and distortion.

Field The experiment is carried out according to the natural scheme. In this case, it is possible to use portable equipment that allows more accurate recording of the received data. The subjects are informed about their participation in the experiment, but the familiar environment reduces the level of motivational distortions.

Depending on the research objectives There are search, pilot and confirmatory experiments. Search the experiment is aimed at finding a cause-and-effect relationship between phenomena. It is carried out at the initial stage of the study, allows you to formulate a hypothesis, identify independent, dependent and secondary variables (see 4.4) and determine ways to control them.

Aerobatic The experiment is a trial experiment, the first in a series. It is conducted on a small sample, without strict control of variables. A pilot experiment allows you to eliminate gross errors in the formulation of a hypothesis, specify the goal, and clarify the methodology for conducting the experiment.

Confirming the experiment is aimed at establishing the type of functional connection and clarifying the quantitative relationships between variables. Conducted at the final stage of the study.

Depending on the nature of influence The test subject is divided into ascertaining, formative and control experiments. Ascertaining an experiment includes measuring the state of an object (a subject or a group of subjects) before active influence on it, diagnosing the initial state, and establishing cause-and-effect relationships between phenomena. Purpose formative experiment is the use of methods for the active development or formation of any properties in subjects. Control An experiment is a repeated measurement of the state of an object (a subject or a group of subjects) and a comparison with the state before the start of the formative experiment, as well as with the state in which the control group was located, which did not receive experimental influence.

By possibilities of influence The experimenter's independent variable is distinguished between the induced experiment and the experiment referred to. Provoked An experiment is an experience in which the experimenter himself changes the independent variable, while the results observed by the experimenter (types of reactions of the subject) are considered provoked. P. Fress calls this type of experiment “classical”. Experiment, which is referred to is an experiment in which changes in the independent variable are carried out without intervention by the experimenter. This type of psychological experiment is resorted to when independent variables have an impact on the subject that is significantly extended over time (for example, the education system, etc.). If the effect on the subject can cause serious negative physiological or psychological impairment, then such an experiment cannot be carried out. However, there are times when a negative impact (such as a brain injury) actually occurs. Subsequently, such cases can be generalized and studied.

4.3. Structure of a psychological experiment

The main components of any experiment are:

1) subject (subject or group being studied);

2) experimenter (researcher);

3) stimulation (the method of influencing the subject chosen by the experimenter);

4) the subject’s response to stimulation (his mental reaction);

5) experimental conditions (in addition to stimulation, influences that can influence the reactions of the subject).

The subject's answer is an external reaction, by which one can judge the processes occurring in his internal, subjective space. These processes themselves are the result of the influence of stimulation and experimental conditions on it.

If the response (reaction) of the subject is denoted by the symbol R, and the influence of the experimental situation on him (as a set of stimulation effects and experimental conditions) is denoted by the symbol S, then their relationship can be expressed by the formula R = =f(S). That is, the reaction is a function of the situation. But this formula does not take into account the active role of the psyche, the human personality (P). In reality, a person’s reaction to a situation is always mediated by the psyche and personality. Thus, the relationship between the main elements of the experiment can be fixed by the following formula: R = f(R, S).

P. Fresse and J. Piaget, depending on the objectives of the study, distinguish three classical types of relationships between these three components of the experiment: 1) functional relationships; 2) structural relations; 3) differential relations.

Functional relationships are characterized by the variability of the responses (R) of the subject (P) with systematic qualitative or quantitative changes in the situation (S). Graphically, these relationships can be represented by the following diagram (Fig. 2).

Examples of functional relationships identified in experiments: changes in sensations (R) depending on the intensity of the impact on the senses (S); memory capacity (R) from the number of repetitions (S); intensity of emotional response (R) on the action of various emotiogenic factors (S); development of adaptation processes (R) in time (S) and so on.

Structural relationships are revealed through a system of responses (R1, R2, Rn) to various situations (Sv S2, Sn). The relationships between individual responses are structured into a system that reflects the structure of personality (P). Schematically it looks like this (Fig. 3).

Examples of structural relationships: a system of emotional reactions (Rp R2, Rn) to the action of stressors (Sv S2, Sn); solution efficiency (R1, R2, Rn) various intellectual tasks (S1, S2, Sn) and so on.

Differential relations are identified through analysis of reactions (R1, R2, Rn) of different subjects (P1, P2, Pn) for the same situation (S). The diagram of these relationships is as follows (Fig. 4).

Examples of differential relationships: differences in reaction speed between different people, national differences in the expressive manifestation of emotions, etc.

To clarify the relationship between all factors included in the experiment, the concept of “variable” was introduced. There are three types of variables: independent, dependent and additional.

Independent variables. A factor that can be changed by the experimenter himself is called independent variable(NP).

The NP in an experiment can be the conditions in which the subject’s activity is carried out, the characteristics of the tasks that the subject is required to perform, the characteristics of the subject himself (age, gender, other differences between the subjects, emotional states and other properties of the subject or people interacting with him). Therefore, it is customary to highlight the following types NP: situational, instructive and personal.

Situational NPs most often are not included in the structure of the experimental task performed by the subject. However, they have a direct impact on his activity and can be varied by the experimenter. Situational NPs include various physical parameters, such as illumination, temperature, noise level, as well as the size of the room, furnishings, placement of equipment, etc. The socio-psychological parameters of situational NPs may include performing an experimental task in isolation, in the presence of an experimenter, an external observer or group of people. V.N. Druzhinin points to the peculiarities of communication and interaction between the subject and the experimenter as a special type of situational NP. Much attention is paid to this aspect. In experimental psychology there is a separate direction called “psychology of psychological experiment”.

Instructional NP are directly related to the experimental task, its qualitative and quantitative characteristics, as well as methods of its implementation. The experimenter can manipulate the instructive NP more or less freely. He can vary the material of the task (for example, numerical, verbal or figurative), the type of response of the subject (for example, verbal or non-verbal), the rating scale, etc. Great possibilities lie in the way of instructing the subjects, informing them about the purpose of the experimental task. The experimenter can change the means that are offered to the subject to complete the task, put obstacles in front of him, use a system of rewards and punishments during the task, etc.

Personal NPs represent controllable characteristics of the subject. Typically, such features are the states of the experiment participant, which the researcher can change, for example, various emotional states or states of performance-fatigue.

Each subject participating in the experiment has many unique physical, biological, psychological, socio-psychological and social characteristics that the experimenter cannot control. In some cases, these uncontrollable characteristics should be considered additional variables and control methods should be applied to them, which will be discussed below. However, in differential psychological research, when using factorial designs, uncontrolled personal variables can act as one of the independent variables (for details on factorial designs, see 4.7).

Researchers also distinguish between different kinds independent variables. Depending on the presentation scales Qualitative and quantitative NPs can be distinguished. High quality NPs correspond to different gradations of naming scales. For example, the emotional states of the subject can be represented by states of joy, anger, fear, surprise, etc. Methods of performing tasks may include the presence or absence of prompts for the subject. Quantitative NPs correspond to rank, proportional or interval scales. For example, the time allotted to complete a task, the number of tasks, the amount of remuneration based on the results of solving problems can be used as quantitative NP.

Depending on the number of manifestation levels independent variables distinguish between two-level and multi-level NPs. Two-level NPs have two levels of manifestation, multi-level– three or more levels. Depending on the number of levels of manifestation of NP, experimental plans of varying complexity are constructed.

Dependent Variables. A factor whose change is a consequence of a change in the independent variable is called dependent variable(ZP). The dependent variable is the component of the subject's response that is of direct interest to the researcher. Physiological, emotional, behavioral reactions and other psychological characteristics that can be recorded during psychological experiments can act as PP.

Depending on the the method by which changes can be registered, allocate salary:

S directly observable;

S requiring physical equipment for measurement;

S requiring a psychological dimension.

To the salary, directly observable include verbal and non-verbal behavioral manifestations that can be clearly and unambiguously assessed by an external observer, for example, refusal of activity, crying, a certain statement by the subject, etc. physical equipment for registration, include physiological (pulse, blood pressure, etc.) and psychophysiological reactions (reaction time, latent time, duration, speed of action, etc.). For POs requiring psychological dimension, include such characteristics as the level of aspirations, the level of development or formation of certain qualities, forms of behavior, etc. For psychological measurement of indicators, standardized procedures can be used - tests, questionnaires, etc. Some behavioral parameters can be measured, i.e. i.e. clearly recognized and interpreted only by specially trained observers or experts.

Depending on the number of parameters, included in the dependent variable, there are unidimensional, multidimensional and fundamental PPs. One-dimensional ZP is represented by a single parameter, changes in which are studied in the experiment. An example of a one-dimensional PP is the speed of a sensorimotor reaction. Multidimensional The salary is represented by a set of parameters. For example, attentiveness can be assessed by the volume of material viewed, the number of distractions, the number of correct and incorrect answers, etc. Each parameter can be recorded independently. Fundamental ZP is a complex variable, the parameters of which have certain known relationships with each other. In this case, some parameters act as arguments, and the dependent variable itself acts as a function. For example, the fundamental dimension of the level of aggression can be considered as a function of its individual manifestations (facial, verbal, physical, etc.).

The dependent variable must have such a basic characteristic as sensitivity. Sensitivity FP is its sensitivity to changes in the level of the independent variable. If, when the independent variable changes, the dependent variable does not change, then the latter is non-positive and it makes no sense to conduct an experiment in this case. There are two known variants of the manifestation of non-positivity of the PP: the “ceiling effect” and the “floor effect”. The “ceiling effect” is observed, for example, in the case when the presented task is so simple that all subjects, regardless of age, perform it. The “floor effect,” on the other hand, occurs when a task is so difficult that none of the subjects can cope with it.

There are two main ways to record changes in mental health in a psychological experiment: immediate and delayed. Direct The method is used, for example, in short-term memory experiments. Immediately after repeating a number of stimuli, the experimenter records their number reproduced by the subject. The deferred method is used when between influence and the effect lasts for a certain period of time (for example, when determining the influence of the number of memorized foreign words on the success of translating a text).

Additional Variables(DP) is a concomitant stimulation of the subject that influences his response. The set of DP consists, as a rule, of two groups: external conditions of experience and internal factors. Accordingly, they are usually called external and internal DPs. TO external DP include the physical environment of the experiment (lighting, temperature, sound background, spatial characteristics of the room), parameters of the apparatus and equipment (design of measuring instruments, operating noise, etc.), time parameters of the experiment (start time, duration, etc.), experimenter's personality. TO internal DP includes the mood and motivation of the subjects, their attitude towards the experimenter and the experiments, their psychological attitudes, inclinations, knowledge, abilities, skills and experience in this type of activity, level of fatigue, well-being, etc.

Ideally, the researcher strives to reduce all additional variables to nothing or at least to a minimum in order to highlight the “pure” relationship between the independent and dependent variables. There are several main ways to control the influence of external DP: 1) elimination of external influences; 2) constancy of conditions; 3) balancing; 4) counterbalancing.

Elimination of external influences represents the most radical method of control. It consists of the complete exclusion from the external environment of any external DP. In the laboratory, conditions are created that isolate the subject from sounds, light, vibrations, etc. The most striking example is a sensory deprivation experiment conducted on volunteers in a special chamber that completely excludes the entry of any irritants from the external environment. It should be noted that it is almost impossible to eliminate the effects of DP, and it is not always necessary, since the results obtained under the conditions of eliminating external influences can hardly be transferred to reality.

The next method of control is to create constant conditions. The essence of this method is to make the effects of DP constant and identical for all subjects throughout the experiment. In particular, the researcher strives to make constant the spatio-temporal conditions of the experiment, the technique of its conduct, equipment, presentation of instructions, etc. With careful application of this method of control, large errors can be avoided, but the problem of transferring the results of the experiment to conditions that are very different from the experimental ones is difficult. remains problematic.

In cases where it is not possible to create and maintain constant conditions throughout the experiment, resort to the method balancing. This method is used, for example, in a situation where the external DP cannot be identified. In this case, balancing will consist of using a control group. The study of the control and experimental groups is carried out under the same conditions with the only difference being that in the control group there is no effect of the independent variable. Thus, the change in the dependent variable in the control group is due only to external DP, while in the experimental group it is due to the combined effect of external additional and independent variables.

If the external DP is known, then balancing consists of the effect of each of its values ​​in combination with each level of the independent variable. In particular, such an external DP as the gender of the experimenter, in combination with an independent variable (the gender of the subject), will lead to the creation of four experimental series:

1) male experimenter - male subjects;

2) male experimenter – female subjects;

3) female experimenter - male subjects;

4) female experimenter - female subjects.

More complex experiments may involve balancing multiple variables simultaneously.

Counterbalancing as a way to control external DP, it is most often practiced when the experiment includes several series. The subject is exposed to different conditions sequentially, but previous conditions can change the effect of subsequent ones. To eliminate the “sequence effect” that arises in this case, experimental conditions are presented to different groups of subjects in different orders. For example, in the first series of the experiment, the first group is presented with solving intellectual problems from simpler to more complex, and the second group - from more complex to simpler. In the second series, on the contrary, the first group is presented with solving intellectual problems from more complex to simpler, and the second group - from simpler to more complex. Counterbalancing is used in cases where it is possible to conduct several series of experiments, but it should be taken into account that a large number of attempts causes fatigue of the subjects.

Internal DP, as mentioned above, are factors hidden in the personality of the subject. They have a very significant impact on the results of the experiment; their impact is quite difficult to control and take into account. Among the internal DPs we can highlight permanent And fickle. Permanent internal DPs do not change significantly during the experiment. If the experiment is carried out with one subject, then the constant internal DP will be his gender, age, and nationality. This group of factors also includes the subject’s temperament, character, abilities, inclinations, interests, views, beliefs and other components of the general orientation of the individual. In the case of an experiment with a group of subjects, these factors acquire the character of unstable internal DPs, and then, to level out their influence, they resort to special methods of forming experimental groups (see 4.6).

TO fickle internal DP includes the psychological and physiological characteristics of the subject, which can either change significantly during the experiment, or be updated (or disappear) depending on the goals, objectives, type, and form of organization of the experiment. The first group of such factors consists of physiological and mental states, fatigue, addiction, and the acquisition of experience and skills in the process of performing an experimental task. The other group includes the attitude towards this experience and this research, the level of motivation for this experimental activity, the attitude of the subject towards the experimenter and his role as a test subject, etc.

To equalize the effect of these variables on responses in different tests, there are a number of methods that have been successfully used in experimental practice.

To eliminate the so-called serial effect, which is based on habituation and uses a special order of stimulus presentation. This procedure is called “balanced alternating order,” when stimuli of different categories are presented symmetrically relative to the center of the stimulus series. The scheme of such a procedure looks like this: A B B A, Where A And IN– incentives of different categories.

To prevent influence on the subject's answer anxiety or inexperience, Introductory or preliminary experiments are carried out. Their results are not taken into account when processing data.

To prevent response variability due to accumulation of experience and skills During the experiment, the subject is offered so-called “exhaustive practice.” As a result of such practice, the subject develops stable skills before the start of the experiment itself, and in further experiments the subject’s performance does not directly depend on the factor of accumulation of experience and skills.

In cases where it is necessary to minimize the influence on the subject’s response fatigue, resort to the “rotation method”. Its essence is that each subgroup of subjects is presented with a certain combination of stimuli. The totality of such combinations completely exhausts the entire set of possible options. For example, with three types of stimuli (A, B, C), each of them is presented with the first, second and third place when presented to the subjects. Thus, the first subgroup is presented with stimuli in the order ABC, the second - AVB, the third - BAV, the fourth - BVA, the fifth - VAB, the sixth - VBA.

The presented methods for procedural equalization of internal non-constant DP are applicable for both individual and group experiments.

The attitude and motivation of the subjects, as internal unstable DPs, must be maintained at the same level throughout the entire experiment. Installation how the willingness to perceive a stimulus and respond to it in a certain way is created through the instructions that the experimenter gives to the subject. In order for the installation to be exactly what is required for the research task, the instructions must be accessible to the subjects and adequate to the objectives of the experiment. The unambiguity and ease of understanding of the instructions are achieved by its clarity and simplicity. To avoid variability in presentation, it is recommended that the instructions be read verbatim or given in writing. Maintenance of the initial setting is controlled by the experimenter through constant observation of the subject and adjusted by reminding, if necessary, the appropriate instructions in the instructions.

Motivation The subject is seen primarily as having an interest in the experiment. If interest is absent or weak, then it is difficult to count on the completeness of the subject’s performance of the tasks provided for in the experiment and on the reliability of his answers. Too much interest, “overmotivation”, is also fraught with inadequacy of the subject’s answers. Therefore, in order to obtain an initially acceptable level of motivation, the experimenter must take the most serious approach to the formation of a contingent of subjects and the selection of factors that stimulate their motivation. Such factors may include competition, various types of remuneration, interest in one’s performance, professional interest, etc.

Psychophysiological conditions It is recommended that subjects not only be maintained at the same level, but also that this level be optimized, i.e., subjects should be in a “normal” state. You should make sure that before the experiment the subject did not have experiences that were extremely significant for him, that he had enough time to participate in the experiment, that he was not hungry, etc. During the experiment, the subject should not be overly excited or suppressed. If these conditions cannot be met, then it is better to postpone the experiment.

From the considered characteristics of the variables and methods of their control, the need for careful preparation of the experiment when planning it becomes clear. In real experimental conditions, it is impossible to achieve 100% control of all variables, but various psychological experiments differ significantly from each other in the degree of control of variables. The next section is devoted to the issue of assessing the quality of the experiment.

The following concepts are used to design and evaluate experimental procedures: ideal experiment, perfect compliance experiment, and infinite experiment.

The perfect experiment is an experiment designed in such a way that the experimenter changes only the independent variable, the dependent variable is controlled, and all other experimental conditions remain unchanged. An ideal experiment assumes the equivalence of all subjects, the invariance of their characteristics over time, and the absence of time itself. It can never be implemented in reality, since in life not only the parameters of interest to the researcher change, but also a number of other conditions.

The correspondence of a real experiment to an ideal one is expressed in such characteristics as internal validity. Internal validity shows the reliability of the results that a real experiment provides compared to an ideal one. The more the changes in the dependent variables are influenced by conditions not controlled by the researcher, the lower the internal validity of the experiment, therefore, the greater the likelihood that the facts discovered in the experiment are artifacts. High internal validity is the main sign of a well-conducted experiment.

D. Campbell identifies the following factors that threaten the internal validity of an experiment: background factor, natural development factor, testing factor, measurement error, statistical regression, non-random selection, screening. If they are not controlled, they lead to the appearance of corresponding effects.

Factor background(history) includes events that occur between the preliminary and final measurement and can cause changes in the dependent variable along with the influence of the independent variable. Factor natural development is due to the fact that changes in the level of the dependent variable may occur due to the natural development of the experiment participants (growing up, increasing fatigue, etc.). Factor testing lies in the influence of preliminary measurements on the results of subsequent ones. Factor measurement errors is associated with inaccuracy or changes in the procedure or method for measuring the experimental effect. Factor statistical regression manifests itself if subjects with extreme indicators of any assessments were selected to participate in the experiment. Factor non-random selection Accordingly, it occurs in cases where, when forming a sample, the selection of participants was carried out in a non-random manner. Factor screening manifests itself when subjects drop out unevenly from the control and experimental groups.

The experimenter must take into account and, if possible, limit the influence of factors that threaten the internal validity of the experiment.

Full Compliance Experiment is an experimental study in which all conditions and their changes correspond to reality. The approximation of a real experiment to a complete correspondence experiment is expressed in external validity. The degree of transferability of the experimental results to reality depends on the level of external validity. External validity, as defined by R. Gottsdancker, affects the reliability of the conclusions that the results of a real experiment provide in comparison with a full compliance experiment. To achieve high external validity, it is necessary that the levels of additional variables in the experiment correspond to their levels in reality. An experiment that lacks external validity is considered invalid.

Factors that threaten external validity include the following:

Reactive effect (consists in a decrease or increase in the susceptibility of subjects to experimental influence due to previous measurements);

The effect of the interaction of selection and influence (consists in the fact that the experimental influence will be significant only for the participants in this experiment);

Factor of experimental conditions (can lead to the fact that the experimental effect can only be observed in these specially organized conditions);

Factor of interference of influences (manifests itself when one group of subjects is presented with a sequence of mutually exclusive influences).

Researchers working in applied areas of psychology - clinical, pedagogical, organizational - are especially concerned about the external validity of experiments, since in the case of an invalid study, its results will not give anything when transferring them to real conditions.

Endless experiment involves an unlimited number of experiments and tests to obtain increasingly accurate results. An increase in the number of trials in an experiment with one subject leads to an increase reliability experimental results. In experiments with a group of subjects, an increase in reliability occurs with an increase in the number of subjects. However, the essence of the experiment is precisely to identify cause-and-effect relationships between phenomena on the basis of a limited number of samples or with the help of a limited group of subjects. Therefore, an endless experiment is not only impossible, but also meaningless. To achieve high reliability of an experiment, the number of samples or the number of subjects must correspond to the variability of the phenomenon being studied.

It should be noted that as the number of subjects increases, the external validity of the experiment also increases, since its results can be transferred to a wider population. To conduct experiments with a group of subjects, it is necessary to consider the issue of experimental samples.

As stated above, an experiment can be carried out either with one subject or with a group of subjects. An experiment with one subject is carried out only in some specific situations. Firstly, these are situations when the individual differences of the subjects can be neglected, i.e., the subject can be any person (if the experiment studies his characteristics in contrast to, for example, an animal). In other situations, on the contrary, the subject is a unique object (a brilliant chess player, musician, artist, etc.). Situations are also possible when the subject is required to have special competence as a result of training or extraordinary life experience (the only survivor of a plane crash, etc.). They are limited to one subject even in cases where repetition of this experiment with the participation of other subjects is impossible. Special experimental designs have been developed for single-subject experiments (see 4.7 for details).

More often, experiments are carried out with a group of subjects. In these cases, the sample of subjects should represent a model general population, to which the results of the study will then be applied. Initially, the researcher solves the problem of the size of the experimental sample. Depending on the purpose of the study and the capabilities of the experimenter, it can range from several subjects to several thousand people. The number of subjects in a separate group (experimental or control) varies from 1 to 100 people. To apply statistical processing methods, it is recommended that the number of subjects in the compared groups be at least 30–35 people. In addition, it is advisable to increase the number of subjects by at least 5-10% of the required number, since some of them or their results will be “rejected” during the experiment.

To select a sample of subjects, several criteria must be taken into account.

1. Meaningful. It lies in the fact that the selection of a group of subjects must correspond to the subject and hypothesis of the study. (For example, it makes no sense to recruit two-year-old children into a group of test subjects to determine the level of voluntary memorization.) It is desirable to create ideal ideas about the object of experimental research and, when forming a group of subjects, to deviate minimally from the characteristics of the ideal experimental group.

2. Equivalence criterion for subjects. When forming a group of subjects, one should take into account all significant characteristics of the research object, differences in the severity of which can significantly affect the dependent variable.

3. Representativeness criterion. The group of individuals participating in the experiment must represent the entire part of the population to which the results of the experiment will be applied. The size of the experimental sample is determined by the type of statistical measures and the selected accuracy (reliability) of accepting or rejecting the experimental hypothesis.

Let's consider strategies for selecting subjects from the population.

Random strategy is that each member of the population is given an equal chance of being included in the experimental sample. To do this, each individual is assigned a number, and then an experimental sample is formed using a table of random numbers. This procedure is difficult to implement, since each representative of the population of interest to the researcher must be taken into account. In addition, the random strategy gives good results when forming a large experimental sample.

Stratometric selection is used if the experimental sample must include subjects with a certain set of characteristics (gender, age, level of education, etc.). The sample is compiled in such a way that it includes equally represented subjects from each stratum (layer) with the given characteristics.

Stratometric random sampling combines the two previous strategies. Representatives of each stratum are assigned numbers and an experimental sample is randomly formed from them. This strategy is effective when selecting a small experimental sample.

Representative modeling is used when the researcher manages to create a model of an ideal object of experimental research. The characteristics of a real experimental sample should deviate minimally from the characteristics of an ideal experimental sample. If the researcher does not know all the characteristics of the ideal model of experimental research, then the strategy is used approximate modeling. The more accurate the set of criteria describing the population to which the conclusions of the experiment are supposed to be extended, the higher its external validity.

Sometimes used as an experimental sample real groups, in this case, either volunteers participate in the experiment, or all subjects are recruited forcibly. In both cases, external and internal validity are violated.

After forming an experimental sample, the experimenter draws up a research plan. Quite often, an experiment is carried out with several groups, experimental and control, which are placed in different conditions. The experimental and control groups should be equivalent at the start of the experimental intervention.

The procedure for selecting equivalent groups and subjects is called randomization. According to a number of authors, group equivalence can be achieved by pairwise selection. In this case, the experimental and control groups are composed of individuals who are equivalent in terms of secondary parameters that are significant for the experiment. The ideal option for pairwise selection is to involve twin pairs. Randomization with identification of strata consists in the selection of homogeneous subgroups in which the subjects are equalized for all characteristics, except for additional variables of interest to the researcher. Sometimes, to isolate a significant additional variable, all subjects are tested and ranked according to the level of its severity. The experimental and control groups are formed so that subjects with the same or similar values ​​of the variable are placed in different groups. The distribution of subjects into experimental and control groups can be carried out by random method. As mentioned above, with a large experimental sample, this method gives quite satisfactory results.

Experimental design is a tactics of experimental research, embodied in a specific system of experimental planning operations. The main criteria for classifying plans are:

Composition of participants (individual or group);

Number of independent variables and their levels;

Types of scales for presenting independent variables;

Method of collecting experimental data;

Place and conditions of the experiment;

Features of the organization of experimental influence and method of control.

Plans for groups of subjects and for one subject. All experimental plans can be divided according to the composition of participants into plans for groups of subjects and plans for one subject.

Experiments with group of subjects have the following advantages: the ability to generalize the results of the experiment to the population; the possibility of using intergroup comparison schemes; saving time; application of statistical analysis methods. The disadvantages of this type of experimental designs include: the influence of individual differences between people on the results of the experiment; the problem of representativeness of the experimental sample; the problem of equivalence of groups of subjects.

Experiments with one subject- this is a special case of “plans with a small N". J. Goodwin points out the following reasons for using such plans: the need for individual validity, since in experiments with a large N A problem arises when the generalized data does not characterize any subject. An experiment with one subject is also carried out in unique cases when, for a number of reasons, it is impossible to attract many participants. In these cases, the purpose of the experiment is to analyze unique phenomena and individual characteristics.

An experiment with small N, according to D. Martin, has the following advantages: the absence of complex statistical calculations, ease of interpretation of results, the ability to study unique cases, the involvement of one or two participants, and ample opportunities for manipulating independent variables. It also has some disadvantages, in particular the complexity of control procedures, difficulty in generalizing results; relative time inefficiency.

Let's consider plans for one subject.

Planning time series. The main indicator of the influence of the independent variable on the dependent variable when implementing such a plan is the change in the nature of the subject’s responses over time. The simplest strategy: scheme A– B. The subject initially performs the activity in conditions A, and then in conditions B. To control the “placebo effect”, the following scheme is used: A – B – A.(“The placebo effect” is the reactions of subjects to “empty” influences that correspond to reactions to real influences.) In this case, the subject should not know in advance which of the conditions is “empty” and which is real. However, these schemes do not take into account the interaction of influences, therefore, when planning time series, as a rule, regular alternation schemes are used (A - B – A– B), positional adjustment (A – B – B– A) or random alternation. The use of “longer” time series increases the possibility of detecting an effect, but leads to a number of negative consequences - fatigue of the subject, decreased control over other additional variables, etc.

Alternative Impact Plan is a development of the time series plan. Its specificity lies in the fact that the effects A And IN are randomly distributed over time and presented to the subject separately. The effects of each intervention are then compared.

Reversible plan used to study two alternative forms of behavior. Initially, a baseline level of manifestation of both forms of behavior is recorded. Then a complex effect is presented, consisting of a specific component for the first form of behavior and an additional one for the second. After a certain time, the combination of influences is modified. The effect of two complex interventions is assessed.

Criteria increasing plan often used in educational psychology. Its essence is that a change in the subject’s behavior is recorded in response to an increase in exposure. In this case, the next impact is presented only after the subject reaches the specified criterion level.

When conducting experiments with one subject, it should be taken into account that the main artifacts are practically unavoidable. In addition, in this case, like no other, the influence of the experimenter’s attitudes and the relationships that develop between him and the subject are manifested.

R. Gottsdanker suggests distinguishing qualitative and quantitative experimental designs. IN quality In plans, the independent variable is presented on a nominative scale, i.e., two or more qualitatively different conditions are used in the experiment.

IN quantitative In experimental designs, the levels of the independent variable are presented on interval, rank or proportional scales, i.e., the experiment uses the levels of expression of a particular condition.

It is possible that in a factorial experiment one variable will be presented in quantitative form and the other in qualitative form. In this case, the plan will be combined.

Within-group and between-group experimental designs. T.V. Kornilova defines two types of experimental plans according to the criterion of the number of groups and experimental conditions: intragroup and intergroup. TO intragroup refers to designs in which the influence of variations in the independent variable and the measurement of the experimental effect occur in the same group. IN intergroup plans, the influence of variants of the independent variable is carried out in different experimental groups.

The advantages of the within-group design are: a smaller number of participants, the elimination of individual differences factors, a reduction in the total time of the experiment, and the ability to prove the statistical significance of the experimental effect. Disadvantages include the non-constancy of conditions and the manifestation of the “sequence effect”.

The advantages of the intergroup design are: the absence of a “sequence effect”, the possibility of obtaining more data, reducing the time of participation in the experiment for each subject, reducing the effect of dropout of experiment participants. The main disadvantage of the between-groups design is the non-equivalence of the groups.

Single independent variable and factorial designs. According to the criterion of the number of experimental influences, D. Martin proposes to distinguish between plans with one independent variable, factorial plans and plans with a series of experiments. In the plans with one independent variable the experimenter manipulates one independent variable, which can have an unlimited number of manifestations. IN factorial plans (for details about them, see p. 120), the experimenter manipulates two or more independent variables, explores all possible options for the interaction of their different levels.

Plans with a series of experiments are carried out to gradually eliminate competing hypotheses. At the end of the series, the experimenter comes to verify one hypothesis.

Pre-experimental, quasi-experimental, and true experimental designs. D. Campbell proposed dividing all experimental plans for groups of subjects into the following groups: pre-experimental, quasi-experimental and true experimental plans. This division is based on the proximity of a real experiment to an ideal one. The fewer artifacts a particular design provokes and the stricter the control of additional variables, the closer the experiment is to ideal. Pre-experimental plans least of all take into account the requirements for an ideal experiment. V.N. Druzhinin points out that they can only serve as illustrations; in the practice of scientific research they should be avoided if possible. Quasi-experimental designs are an attempt to take into account the realities of life when conducting empirical research; they are specifically created to deviate from the designs of true experiments. The researcher must be aware of the sources of artifacts - external additional variables that he cannot control. A quasi-experimental design is used when a better design cannot be used.

Systematic features of pre-experimental, quasi-experimental and true experimental designs are given in the table below.

When describing experimental plans, we will use the symbolization proposed by D. Campbell: R– randomization; X– experimental influence; O– testing.

TO pre-experimental designs include: 1) single case study; 2) plan with preliminary and final testing of one group; 3) comparison of statistical groups.

At single case study One group is tested once after the experimental intervention. Schematically, this plan can be written as:

Control of external variables and independent variable is completely absent. In such an experiment there is no material for comparison. The results can only be compared with everyday ideas about reality; they do not carry scientific information.

Plan with preliminary and final testing of one group often used in sociological, socio-psychological and pedagogical research. It can be written as:

This design does not have a control group, so it cannot be argued that changes in the dependent variable (the difference between O1 and O2), recorded during testing, are caused precisely by changes in the independent variable. Between the initial and final testing, other “background” events may occur that affect the subjects along with the independent variable. This design also does not control for the natural progression effect and the testing effect.

Comparison of statistical groups it would be more accurate to call it a two-non-equivalent group design with post-exposure testing. It can be written like this:

This design allows for the testing effect to be taken into account by introducing a control group to control for a number of external variables. However, with its help it is impossible to take into account the effect of natural development, since there is no material to compare the state of the subjects at the moment with their initial state (preliminary testing was not carried out). To compare the results of the control and experimental groups, Student's t-test is used. However, it should be taken into account that differences in test results may not be due to experimental effects, but to differences in group composition.

Quasi-experimental designs are a kind of compromise between reality and the strict framework of true experiments. There are the following types of quasi-experimental designs in psychological research: 1) experimental plans for non-equivalent groups; 2) designs with pre-test and post-test of different randomized groups; 3) plans of discrete time series.

Plan experiment for non-equivalent groups is aimed at establishing a cause-and-effect relationship between variables, but it does not have a procedure for equalizing groups (randomization). This plan can be represented by the following diagram:

In this case, two real groups are involved in conducting the experiment. Both groups are tested. One group is then exposed to the experimental treatment while the other is not. Both groups are then retested. The results of the first and second testing of both groups are compared; Student’s t-test and analysis of variance are used for comparison. Difference O2 and O4 indicates natural development and background exposure. To identify the effect of the independent variable, it is necessary to compare 6(O1 O2) and 6(O3 O4), i.e., the magnitude of the shifts in the indicators. The significance of the difference in the increases in indicators will indicate the influence of the independent variable on the dependent one. This design is similar to the design of a true two-group experiment with pre- and post-exposure testing (see page 118). The main source of artifacts is differences in group composition.

Plan with pre- and post-testing of different randomized groups differs from a true experimental design in that one group is pretested and an equivalent group is exposed to the posttest:

The main disadvantage of this quasi-experimental design is the inability to control for background effects—the influence of events that occur alongside the experimental treatment between the first and second testing.

Plans discrete time series are divided into several types depending on the number of groups (one or several), as well as depending on the number of experimental effects (single or series of effects).

The discrete time series design for one group of subjects consists of initially determining the initial level of the dependent variable on a group of subjects using a series of sequential measurements. Then an experimental effect is applied and a series of similar measurements are carried out. The levels of the dependent variable before and after the intervention are compared. The outline of this plan:

The main disadvantage of a discrete time series design is that it does not allow one to separate the effect of the independent variable from the effect of background events that occur during the course of the study.

A modification of this design is a time-series quasi-experiment in which exposure before measurement is alternated with no exposure before measurement. His scheme is as follows:

ХO1 – O2ХO3 – O4 ХO5

Alternation can be regular or random. This option is only suitable if the effect is reversible. When processing the data obtained in the experiment, the series is divided into two sequences and the results of measurements where there was an impact are compared with the results of measurements where there was no impact. To compare data, Student's t-test with the number of degrees of freedom is used n– 2, where n– the number of situations of the same type.

Time series plans are often implemented in practice. However, when using them, the so-called “Hawthorne effect” is often observed. It was first discovered by American scientists in 1939, when they conducted research at the Hawthorne plant in Chicago. It was assumed that changing the labor organization system would increase productivity. However, during the experiment, any changes in the organization of work led to an increase in productivity. As a result, it turned out that participation in the experiment itself increased motivation to work. The subjects realized that they were personally interested in them and began to work more productively. To control for this effect, a control group must be used.

The time series design for two non-equivalent groups, one of which receives no intervention, looks like this:

O1O2O3O4O5O6O7O8O9O10

O1O2O3O4O5O6O7O8O9O10

This plan allows you to control the “background” effect. It is usually used by researchers when studying real groups in educational institutions, clinics, and production.

Another specific design that is often used in psychology is called an experiment. ex-post-facto. It is often used in sociology, pedagogy, as well as neuropsychology and clinical psychology. The strategy for applying this plan is as follows. The experimenter himself does not influence the subjects. The influence is some real event from their life. The experimental group consists of “test subjects” who were exposed to the intervention, and the control group consists of people who did not experience it. In this case, the groups are, if possible, equalized at the time of their state before the impact. Then the dependent variable is tested among representatives of the experimental and control groups. The data obtained as a result of testing are compared and a conclusion is drawn about the impact of the impact on the further behavior of the subjects. Thus the plan ex-post-facto simulates an experimental design for two groups with their equalization and testing after exposure. His scheme is as follows:

If group equivalence can be achieved, then the design becomes a true experimental design. It is implemented in many modern studies. For example, in the study of post-traumatic stress, when people who have suffered the effects of a natural or man-made disaster, or combatants, are tested for the presence of PTSD, their results are compared with the results of a control group, which makes it possible to identify the mechanisms of such reactions. In neuropsychology, brain injuries, lesions of certain structures, considered as “experimental exposure,” provide a unique opportunity to identify the localization of mental functions.

True Experiment Plans for one independent variable differ from others as follows:

1) using strategies to create equivalent groups (randomization);

2) the presence of at least one experimental and one control group;

3) final testing and comparison of the results of groups that received and did not receive the intervention.

Let's take a closer look at some experimental designs for one independent variable.

Two randomized group design with post-exposure testing. His diagram looks like this:

This plan is used if it is not possible or necessary to conduct preliminary testing. If the experimental and control groups are equal, this design is the best because it allows you to control most sources of artifacts. The absence of pretesting excludes both the interaction effect of the testing procedure and the experimental task, as well as the testing effect itself. The plan allows you to control the influence of group composition, spontaneous attrition, the influence of background and natural development, and the interaction of group composition with other factors.

In the example considered, one level of influence of the independent variable was used. If it has several levels, then the number of experimental groups increases to the number of levels of the independent variable.

Two randomized group design with pretest and posttest. The outline of the plan looks like this:

R O1 X O2

This design is used if there is doubt about the results of randomization. The main source of artifacts is the interaction of testing and experimental manipulation. In reality, we also have to deal with the effect of non-simultaneous testing. Therefore, it is considered best to test members of the experimental and control groups in random order. Presentation-non-presentation of the experimental intervention is also best done in random order. D. Campbell notes the need to control “intra-group events.” This experimental design controls well for the background effect and the natural progression effect.

When processing data, parametric criteria are usually used t And F(for data on an interval scale). Three t values ​​are calculated: 1) between O1 and O2; 2) between O3 and O4; 3) between O2 And O4. The hypothesis about the significance of the influence of the independent variable on the dependent variable can be accepted if two conditions are met: 1) differences between O1 And O2 significant, but between O3 And O4 insignificant and 2) differences between O2 And O4 significant. Sometimes it is more convenient to compare not absolute values, but the magnitude of the increase in indicators b(1 2) and b(3 4). These values ​​are also compared using Student's t test. If the differences are significant, the experimental hypothesis about the influence of the independent variable on the dependent variable is accepted.

Solomon's Plan is a combination of the two previous plans. To implement it, two experimental (E) and two control (C) groups are needed. His diagram looks like this:

This design can control for the pretest interaction effect and the experimental effect. The effect of experimental influence is revealed by comparing the indicators: O1 and O2; O2 and O4; O5 and O6; O5 and O3. Comparison of O6, O1 and O3 allows us to identify the influence of the factor of natural development and background influences on the dependent variable.

Now consider a design for one independent variable and several groups.

Design for three randomized groups and three levels of the independent variable used in cases where it is necessary to identify quantitative relationships between independent and dependent variables. His diagram looks like this:

In this design, each group is presented with only one level of the independent variable. If necessary, you can increase the number of experimental groups in accordance with the number of levels of the independent variable. All of the above statistical methods can be used to process the data obtained using such an experimental design.

Factorial experimental designs used to test complex hypotheses about relationships between variables. In a factorial experiment, as a rule, two types of hypotheses are tested: 1) hypotheses about the separate influence of each of the independent variables; 2) hypotheses about the interaction of variables. A factorial design involves all levels of independent variables being combined with each other. The number of experimental groups is equal to the number of combinations.

Factorial design for two independent variables and two levels (2 x 2). This is the simplest of factorial designs. His diagram looks like this.

This design reveals the effect of two independent variables on one dependent variable. The experimenter combines possible variables and levels. Sometimes four independent randomized experimental groups are used. To process the results, Fisher's analysis of variance is used.

There are more complex versions of the factorial design: 3 x 2 and 3 x 3, etc. The addition of each level of the independent variable increases the number of experimental groups.

"Latin Square". It is a simplification of a complete design for three independent variables having two or more levels. The Latin square principle is that two levels of different variables occur only once in an experimental design. This significantly reduces the number of groups and the experimental sample as a whole.

For example, for three independent variables (L, M, N) with three levels each (1, 2, 3 and N(A, B, C)) the plan using the “Latin square” method will look like this.

In this case, the level of the third independent variable (A, B, C) occurs once in each row and each column. By combining results across rows, columns, and levels, it is possible to identify the influence of each of the independent variables on the dependent variable, as well as the degree of pairwise interaction between the variables. Application of Latin letters A, B, WITH It is traditional to designate the levels of the third variable, which is why the method is called “Latin square”.

"Greco-Latin square". This design is used when the influence of four independent variables needs to be examined. It is constructed on the basis of a Latin square for three variables, with a Greek letter attached to each Latin group of the design, indicating the levels of the fourth variable. A design for a design with four independent variables, each with three levels, would look like this:

To process the data obtained in the “Greco-Latin square” design, the Fisher analysis of variance method is used.

The main problem that factorial designs can solve is determining the interaction of two or more variables. This problem cannot be solved using several conventional experiments with one independent variable. In a factorial design, instead of trying to “cleanse” the experimental situation of additional variables (with a threat to external validity), the experimenter brings it closer to reality by introducing some additional variables into the category of independent ones. At the same time, the analysis of connections between the studied characteristics allows us to identify hidden structural factors on which the parameters of the measured variable depend.

The theory of correlation research was developed by the English mathematician K. Pearson. The strategy for conducting such a study is that there is no controlled impact on the object. The design of a correlational study is simple. The researcher puts forward a hypothesis about the presence of a statistical connection between several mental properties of an individual. In this case, the assumption of causal dependence is not discussed.

Correlation is a study conducted to confirm or refute a hypothesis about a statistical relationship between several (two or more) variables. In psychology, mental properties, processes, states, etc. can act as variables.

Correlation connections.“Correlation” literally means ratio. If a change in one variable is accompanied by a change in another, then we talk about the correlation of these variables. The presence of a correlation between two variables does not indicate the presence of cause-and-effect relationships between them, but makes it possible to put forward such a hypothesis. The lack of correlation allows us to refute the hypothesis about the cause-and-effect relationship of the variables.

There are several types of correlations:

Direct correlation (the level of one variable directly corresponds to the level of another variable);

Correlation due to a third variable (the level of one variable corresponds to the level of another variable due to the fact that both of these variables are due to a third, common variable);

Random correlation (not due to any variable);

Correlation due to heterogeneity of the sample (if the sample consists of two heterogeneous groups, then a correlation may be obtained that does not exist in the general population).

Correlation connections are of the following types:

– positive correlation (an increase in the level of one variable is accompanied by an increase in the level of another variable);

– negative correlation (an increase in the level of one variable is accompanied by a decrease in the level of another);

– zero correlation (indicates that there is no connection between the variables);

– nonlinear relationship (within certain limits, an increase in the level of one variable is accompanied by an increase in the level of another, and for other parameters, vice versa. Most psychological variables have a nonlinear relationship).

Designing a correlational study. A correlational research design is a type of quasi-experimental design in which the independent variable does not influence the dependent variables. A correlation study is divided into a series of independent measurements in a group of subjects. When simple In a correlation study, the group is homogeneous. When comparative In a correlation study, we have several subgroups that differ in one or more criteria. The results of such measurements give a matrix of the form R x O. Data from a correlation study is processed by calculating correlations along the rows or columns of the matrix. Row correlation provides a comparison between subjects. Column correlation provides information about the relationship between measured variables. Temporal correlations are often detected, i.e., changes in the structure of correlations over time.

The main types of correlational research are discussed below.

Comparison of two groups. It is used to establish the similarity or difference between two natural or randomized groups in terms of the severity of a particular parameter. The mean results of the two groups are compared using Student's t test. If necessary, Fisher's t-test can also be used to compare the variances of the indicator in two groups (see 7.3).

Univariate study of one group in different conditions. The design of this study is close to experimental. But in the case of correlation research, we do not control the independent variable, but only note the change in the individual’s behavior under different conditions.

Correlation study of pairwise equivalent groups. This design is used in twin studies using intrapair correlations. The twin method is based on the following provisions: the genotypes of monozygotic twins are 100% similar, and dizygotic twins are 50% similar, the development environment of both dizygotic and monozygotic pairs is the same. Dizygotic and monozygotic twins are divided into groups: each group contains one twin from the pair. The parameter of interest to the researcher is measured in twins of both groups. Then the correlations between the parameters are calculated (ABOUT-correlation) and between twins (R-correlation). By comparing intrapair correlations of monozygotic and dizygotic twins, it is possible to identify the shares of the influence of environment and genotype on the development of a particular trait. If the correlation of monozygotic twins is reliably higher than the correlation of dizygotic twins, then we can talk about the existing genetic determination of the trait, otherwise we talk about environmental determination.

Multivariate correlation study. It is carried out to test the hypothesis about the relationship between several variables. An experimental group is selected and tested according to a specific program consisting of several tests. The research data is entered into a table of “raw” data. This table is then processed and linear correlation coefficients are calculated. Correlations are assessed for statistical differences.

Structural correlation study. The researcher identifies differences in the level of correlations between the same indicators measured in representatives of different groups.

Longitudinal correlational study. It is built according to a time series plan with testing of the group at specified intervals. Unlike a simple longitudinal study, the researcher is interested in changes not so much in the variables themselves as in the relationships between them.

The essence of the experimental method is to test a scientific hypothesis using controlled conditions of the subject's activity. Based on the available data, an assumption is made about how the animal will behave in certain, specially organized conditions and how a change in these conditions will affect the change in the behavior of the subject. Hypotheses can be exploratory, alternative, clarifying, etc. An experiment differs from an observation in that there is active intervention in the situation on the part of the experimenter. When conducting an experiment, various devices, apparatus and installations can be used, both corresponding and not corresponding to the natural living conditions of animals. Various devices can be used to capture data.

BASIC PRINCIPLES OF THE EXPERIMENTAL METHOD

1. Controllability of conditions and behavior of the subject . When conducting an experiment, it is necessary to take into account all the features of the situation and the capabilities of the animal. This is not always easy to do, since animals, unlike humans, cannot be given instructions and rely on their conscious execution. Therefore, the experimental situation should be designed in such a way as to minimize unexpected reactions of the animals. In all cases, such reactions are recorded in the observation protocol and are used to interpret the data obtained. In animal psychology, there are often cases when an animal, especially one with a highly developed psyche, reacts to an experimental situation differently than the researcher expected. For example, in W. Köhler's experiments, chimpanzees were asked to reach a high-hanging bait using a stick, which the researcher assumed the monkey would hold in his hand. However, in some cases, the chimpanzees used the stick as a jumping pole or quickly climbed onto it, placing it vertically under the bait. It turned out that it is sometimes more difficult for a monkey to manipulate a long stick while standing than to use it as a device for locomotion. In experiments using a stick to roll bait out of a simple maze, chimpanzees and orangutans consistently used a number of methods not taken into account by scientists, which had to be consistently eliminated in order to test the hypothesis. The monkeys, instead of rolling the bait along the passages of the maze with a stick, threw the bait over the side of the maze, prying it up with a stick, dragged it, pressing it against the side with a stick, and even accurately hit the experimental table from below, as a result of which the bait jumped up and fell over the side of the maze . Orangutans behaved in a similar way when they were asked to push the bait out of the tube with a stick. They shook out the bait, knocking the tube on the floor, and even blew it out with their mouth, rolled out and kneaded the tube on the floor, etc. Thus, the very process of the animal’s activity changed: it had to not get the bait in the only possible way, following from the situation itself, but find the method that was permitted and reinforced by the experimenter. Research by almost all scientists who have studied and are studying the psyche of higher animals, and especially monkeys, indicates that in a number of cases we are dealing with just such a situation, i.e. We study not the animal’s ability to act in a proposed objective situation, but its ability to identify a task posed by a person and find an appropriate solution. Therefore, the requirement to control the experimental conditions and the behavior of the animal is one of the most important and at the same time difficult to implement principles of conducting an experiment.

2. Availability of a specially developed procedure for conducting an experiment and recording the data obtained. This principle reflects the essence of the experimental method. For each experiment, a procedure is specially developed, which includes the sequence of all events and actions of the experimenter and the subject, a description of the recorded forms of animal behavior and the method of such recording. The received data is processed in a specially developed way. This allows you to compare data obtained in different series of experiments and by different researchers, which ensures their reliability and objectivity.

3. Possibility of repeating the experiment with the same and other animals, as well as other researchers. When conducting an experiment and presenting the data obtained, it is mandatory to present the methodology and results in such a form that they can be assessed and, if necessary, repeated by other researchers. This is what allows us to ultimately understand the causes and mechanisms of animal behavior. Often, researchers using the same technique obtain different results, the comparison of which makes it possible to identify the true characteristics of the psyche of the animals being studied.

4. Objectivity. This principle involves accurate recording and unbiased interpretation of animal behavior, regardless of whether it corresponds to the researcher’s hypothesis. Animal psychology, like any science in general, unfortunately, is not free from either the ideological or personal characteristics of the researcher. Therefore, objective recording of data, a detailed presentation of the methodology, the availability and safety of observation and experimental protocols are mandatory and necessary in zoopsychological research.

Stage I - diagnostic - analysis of the difficulties of specialists, clients, the state of the problem, identification and formulation of contradictions that need to be eliminated as quickly as possible with the help of any changes. In other words: identifying the problem and justifying its relevance.

Stage II – prognostic – setting a goal, defining tasks, building a model of a new technology (methodology, structure, system of measures...), formulating a hypothesis, predicting expected results (positive and negative), inventing auxiliary mechanisms. In other words: development of an extensive experimental program.

diagnostic and pre-experimental stages.

prognostic stages

Include:

- identification of unresolved problems;

- selection of the topic of this research (specification);

- setting the goals and objectives of the study;

- study of real practice in solving this problem;

- study of measures existing in theory and practice that help solve the problem

- formulating a research hypothesis.

Stage III – organizational . Organization of experimental work. An important stage, because If the experiment is poorly organized, negative results can occur even with a well-thought-out methodology.

This stage includes:

Drawing up an experiment program. We'll look at it a little later).

Providing conditions for the implementation of the program:

- preparation of material resources;

- distribution of management functions: who is responsible for what: the director, his deputies, others and participants;

- organization of special training of personnel.

3. Methodological support. First of all, this includes preparing the program. But that's not all. This includes the preparation of the necessary teaching materials, questionnaires, a written or oral detailed presentation of the technology itself, each element, and its scientific foundations. The leader prepares everything.

It is important to consider the moral and material incentives for the specialists conducting the experiment.

4. Selection (justification) of experimental and control objects (parallels, classes, individual students, associations, etc.). There must be equivalence in terms of initial parameters.

5. Search, selection, attraction of a scientific supervisor or consultant. This is not necessary, but it is desirable, because it significantly speeds up the preparation of the program. These could be scientists, university teachers, IPK, school teachers with an academic degree, etc.

Thus, the organizational stage includes the preparation and conduct of the experiment:

– selection of the required number of experimental objects,

– determination of the required duration of the experiment,

– selection of specific methods for studying the initial state of the experimental object, questionnaires, interviews, to create appropriate situations, expert assessment, etc.,

– testing the availability and effectiveness of methods on a small number of subjects,

– determination of signs by which one can judge changes in the experimental object under the influence of relevant influences.

Stage IV - practical - carrying out initial ascertaining sections, implementing a new technology, tracking the process, intermediate results, adjusting the technology being tested, control tests.

Conducting an experiment to test the effectiveness of a certain system of measures includes:

– study of the initial state of the system in which the experiment is carried out;

– study of the initial state of the conditions in which the experiment is carried out;

– assessment of the conditions of the participants themselves;

– formulation of criteria for the effectiveness of the proposed system of measures;

– instructing experiment participants on the procedure and conditions for its effective implementation (if the experiment is conducted by more than one specialist);

– recording data on the progress of the experiment based on intermediate sections characterizing changes in objects under the influence of the experimental system of measures;

– indication of difficulties and possible typical shortcomings during the experiment;

– assessment of the current costs of time, money and effort.

Stage V – generalizing – data processing, correlation of the experiment results with the set goals, analysis of all results, adjustment of the hypothesis, models of the new technology in accordance with the result, design and description of the progress and results of the experiment.

The summary of the experiment includes:

– description of the results of the implementation of the experimental system of measures (final state of activity, level of education, etc.);

– characteristics of the conditions under which the experiment gave favorable results (educational and material, hygienic, moral and psychological, etc.);

– description of the characteristics of the subjects of experimental influence (specialists, educators, etc.);

– data on the expenditure of time, effort and money;

– indication of the limits of application of the system of measures tested during the experiment.

Stage VI – implementation – dissemination of a new technique (or implementation as a controlled process) in a team, directed organization of experience in implementing experience developed by other specialists.

Stages of the experiment

Stater. The goal is to “make a copy”, to build a schematic model of the phenomenon that is to be studied. It can be carried out not only at the beginning of the study, but also during it to detect sections after a certain time, when experimentally introduced conditions or influences were in effect.

This is a preliminary study of the state of the problem. The second stage follows from this.

Formative (constructing, creating, transforming). Its task is to test and confirm (or exclude) the hypothesis. (The task of pedagogical research is to reveal the dependencies, laws, and causes that cause the phenomenon being studied.) Without it, the psychological and pedagogical experiment remains incomplete. Based on the analysis of the results obtained at the first stage, the researcher formulates and refines the hypothesis. Next, he checks it by constructing the activity in a new way, i.e. introducing a condition that should ensure an increase in the efficiency of the work being carried out. The found feature is clarified on a large number of study groups. But to prove the decisive role of a new experimental component, the experiment is often carried out in several groups (experimental and control). To obtain “pure” results, the researcher seeks to equate these groups (by composition, age of clients, their social status).

The transformative stage of the experiment allows the researcher to actively change the content and form of life of the team (and each client) in accordance with the hypothesis and goals.

Control (stating) – quantitative and qualitative differences between the experimental and control groups are identified. The advantages of the former are manifested in more efficient performance even of those clients who at the beginning of the experiment gave average or low performance.

Preparation of the experiment program:

Justification of the topic (relevance), its formulation.

Object, subject, goal, objectives, hypothesis.

Selection of specific research techniques and methods.

Deadlines, take into account reserve time.

1. Criteria for assessing expected exam results.

   Forecasting when preparing an experiment. What we mean here is that we expect, foresee, forecast:

possible (expected) positive results;

possible losses, negative consequences;

compensation for these losses and consequences.

Depending on the specifics of the experiment, the following types of experiments are used:

Laboratory– carried out in specially created conditions. Requires the use of special equipment. (It is rarely used in pedagogy.) In recent years, its version has begun to be used, which is a simplified, “chamber” version. It is carried out with each subject separately, and he works with familiar materials: cards, geometric shapes, puzzle constructors...

Natural– carried out under familiar conditions. Work with the client is carried out either by a specialist or a person familiar to him. The process of activity itself is also natural: completing written tasks, answering questions verbally. This method can be used by a well-trained theoretical specialist.

But the possibilities of a natural experiment in terms of proving open dependencies are small. Therefore, it must be combined with its other types, in particular with various types of psychological and pedagogical experiment. (It is carried out within the framework of a natural experiment).

Psychological and pedagogical experiment(developed on the basis of the natural) - active, purposeful study of individual aspects of the educational process, behavior, and relationships of students in the team. As a rule, he states states, qualities, personality traits, as if imprinting, fixing the process at a certain stage of the study.

Its features:

– focus on studying the question posed through the active influence of the researcher on the course of the phenomenon being studied. In this case, the psychological and pedagogical experiment “constructs”, forms new qualities and properties, changing the existing conditions, and creates new ones;

– the ability to strictly control everything new and evaluate the obtained qualitative and quantitative results.

According to the duration of the experimental conditions:

- long lasting;

- short-term.

According to the structure of the social phenomena being studied:

- simple;

- difficult.

The concept appears in the literature pilot experiment. It is more often called preliminary. Its appearance is due to the fact that any experiment must be carefully prepared. To do this, the level of elaboration and quality of the experimental methodology is checked in practice. Such a preliminary experiment is first carried out not in full, but in an abbreviated version. This is a pilot experiment.

Its purpose is to test and bring the experimental methodology to a high level. After this, individual parts of the experiment or its fragments are corrected. And only then the experiment is organized in full.

In sociological research, the concept of “field experiment” is encountered. This is an experiment when an object (group) is in the natural conditions of its functioning. In this case, group members may or may not be aware that they are participating in an experiment. The decision about awareness in each specific case depends on how much this awareness can influence the course of the experiment.

In the social sphere, the so-called social experiment plays a special role.

Social experiment – a method of studying social phenomena and processes, carried out by observing changes in a social object under the influence of factors that control and direct its development.

A social experiment involves:

– making changes to existing relationships;

– monitoring the impact of changes on the activities and behavior of individuals and social groups;

– analysis and evaluation of the results of this influence.

Social experiments also include attempts to create groups that live according to principles that differ from those generally accepted in the surrounding society (usually on an ideological or religious basis).

Questions for self-control:

What is experiment as a method of scientific research?

What are the conditions for the effectiveness of an experiment?

What types of experiments are used in scientific research? What are their features?

What are the stages of organizing an experiment?

What are the stages of an experiment?

What should a researcher pay attention to when forming experimental and control groups for an experiment?

What are the specifics of conducting an experiment in social work? Its advantages and limitations.

What mistakes should be avoided when preparing and conducting an experiment?

What is a social experiment?

In order to understand how the experimental study of personality traits differs from any other type of research, let's look at what an experiment is and what are the basic principles of conducting experiments...

The purpose of any experiment is to test hypotheses about the causal relationship between phenomena: the researcher creates or seeks a certain situation, activates a hypothetical cause and observes changes in the natural course of events, recording their compliance or non-compliance with assumptions and hypotheses.

It must be said that experiment as a method of empirical research began to be actively used only in the 20s of this century. And to this day, experiments in psychology and sociology are quite complex for the simple reason that the organizational problems associated with conducting an experiment are quite complex and troublesome, and many processes are still poorly understood to advance explanatory hypotheses. In this situation, in order to increase the degree of scientific validity of the results of such a study, it is necessary to conduct repeated experiments, using different types. What types are there?

Social experiments differ: 1) by the nature of the object and subject of research, 2) by the specifics of the task, 3) by the nature of the experimental situation, 4) by the logical structure of the proof of the hypothesis.

According to the nature of the object and subject of research, one should distinguish between sociological, economic (economic), legal, socio-psychological, pedagogical, psychological, and aesthetic experiments. The differences between these types of experiments are determined by the specifics of the relevant scientific disciplines, however, in some cases, different types of experiments can be closely interrelated, based on the same processes of reality.

The nature of the research object also differs real And mental experiments. If in a real experiment explanatory hypotheses are tested by systematically controlling the conditions of social activity, then in a thought experiment it is not real phenomena that are tested, but information about them. Due to the fact that a thought experiment lacks a very important sign of experimentation - purposeful intervention in real processes, transformation of an object by introducing an experimental factor, many researchers do not consider it among the varieties of social experiment.

According to the specifics of the task at hand, they differ:

1) Scientific And applied experiments. Scientific experiments are aimed at acquiring new knowledge, while applied experiments are aimed at obtaining a practical effect.

2) Projective And retrospective. Projective experiments are aimed at the future: the researcher designs the manifestations of the intended consequences by introducing hypothetical causes. Retrospective - directed to the past: the researcher manipulates information about past events, tries to test hypotheses about the causes that caused the existing consequences.

3) One- And multi-factor experiments. In a single-factor experiment, a hypothesis about the consequences of the influence of one independent variable is tested, in a multifactorial experiment, a whole complex of variables in their interaction is tested.

According to the nature of the experimental situation, one should first of all distinguish controlled And uncontrolled experiments. The results of uncontrolled experiments are significantly influenced by extra-experimental factors, the nature and degree of influence of which are unknown, and the very nature of these factors often remains unknown. In a controlled experiment, controlling variables means equalizing all conditions on the experimental and control objects, except for the influence of the experimental factor, and periodically measuring the values ​​of both experimental and non-experimental variables. (It should be noted that such an experiment in sociology is practically impossible).

Attempts to conduct a controlled experiment usually lead to an experiment laboratory, that is, to such an experiment when they try to artificially create conditions that are as close as possible to both the research objectives and the real situation . One of the central problems of such an experiment is the correct introduction to the experiment, the correct instructions: 1) an explanation of the goals of the experiment (why all this is being done), 2) an explanation of the tasks of the subjects (what they should do), 3) a call for normal calm behavior “as always ".

In a field experiment, the situation under the influence of the experimental factor is much closer to natural conditions, but at the same time much less manageable and controllable.

Among field experiments there are differences actively directed And natural. An experiment in which the researcher is active is considered actively directed: he introduces an experimental factor, which, according to his hypothesis, should lead to certain consequences. Plus, the researcher strives to ensure that the subjects do not know about the experiment being conducted. In a natural experiment, the factor being studied is not introduced by the experimenter; its effect is caused by the natural course of events. The researcher is looking for a suitable situation where the experimental factor is only in maximum natural isolation from other factors and only observes the development of events before and after the influence of the factor being studied, recording them as far as possible. It should be noted that it remains controversial whether such studies are a type of experiment or observation. Many essential features of an experiment are absent (researcher activity, control of variables), but the explanatory hypothesis and the logical scheme of its proof remain.

In addition to the above, experiments can also differ in the logical structure of proving a hypothesis. In this case they are divided into parallel (simultaneous) And sequential (successive) experiments.

In a parallel experiment, the proof relies on comparing the states of two objects, experimental and control (in social research, this is usually an experimental and control group of people) at the same time. In this case, the experimental group is the one that was influenced by the experimental factor, and the control group is the group that was not influenced.

In a sequential experiment there is no control group. The same group serves as a control group before the introduction of the experimental factor and as an experimental group after the factor has (or could have) the expected effect.

Now that we have figured out what an experiment is, let's try to figure out what personality traits are and what they are.