Lecture
- Reference to a particular subject area (an experiment in the sphere of the psychology of perception, motivation, etc.);
- The real and the thought experiment;
- Natural, artificial, and laboratory experiments.
This criterion of classification is set by the differences among independent variables from the standpoint of their correspondence to the conditions of a person’s real life activity or to theoretical concepts operationalized at the level of concrete methodological means.
In any case, the experimental conditions are constructed as experimental models that represent the cause-and-effect relationships under study.
In a laboratory experiment, the experimental model (EM) realizes those conceptions of the relationship between the IV and the DV which represent the psychological constructs stated in the scientific theoretical hypothesis.
Laboratory experiments, like artificial ones, are conducted under specially created conditions. They presuppose a purification of the experimental conditions so that single independent variables can be changed. Example: an experiment with dichotic listening on the distribution of attention. In reality, its analogue is the «cocktail party», but this presupposes binaural hearing rather than the arrival of a separate information channel in each ear. The artificiality here is justified by the aim, which consists in testing a scientifically grounded model, i.e. here a transfer of the generalization to the world of theory is presupposed.
Artificial experiments: the experimental situation models a real one but allows for better control of the relationship between the dependent and independent variables by eliminating or stabilizing a number of extraneous variables that are usually present under real conditions of life activity.
The distinctive feature of the EM in artificial experiments is that the IVs in them function as complex variables, while some of the additional and extraneous variables are taken outside the bounds of the EM (for example, motivational factors).
The difference between artificial and laboratory experiments lies in what the experimental model represents: a real situation or a theoretical model. This difference can be traced in the forms in which artificial and laboratory experiments are conducted: in the former case, games and simulators, where the purification of conditions must not affect the quality of the process under study.
It was precisely artificial experiments that Gottsdanker called «improving the world».
They are conducted in the case where a simple reproduction of the real situation does not make it possible to render the experiment internally valid. However, a question arises: can the results of such an experiment be applied to reality? Thus the problem of external validity comes to the fore.
Examples of artificial experiments (Gottsdanker):
- Pilots. Hypothesis: when landing an aircraft on gradually rising terrain, pilots experience a visual illusion, and therefore they descend too steeply. The first way of improving reality: eliminating systematic confounding.
- Rescuers. The success of a search with 7x50 binoculars and without them is compared. The second way of improving reality: more data means higher reliability.
- Comparison of altimeters. The third way of improving reality: high reliability through the reduction of non-systematic variability.
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