An experiment is an important part of research in which a phenomenon is examined under conditions controlled by the researcher. This term is widely known, as it is used in a variety of sciences (mainly in natural sciences). However, the term "quasi-experiment" is not familiar to everyone. What is it and what are the features of this type of experiment? Let's try to make it out in the article.
Who is the author of the term?
This word was introduced into scientific circulation by D. Campbell, an American psychologist, philosopher and sociologist. He first used it in his book Models of Experiments in Social Psychology and Applied Research. In it, he describes the main problems associated with the collection of qualitative and quantitative knowledge, the main models of research (this is where he uses the term "quasi-experiment"), as well as some applied problems in the social sciences. The concept was introduced in order to solve the problems faced by psychologists who sought to study various problems not instrict laboratory conditions, but in reality.
Quasi-experiment - what is it?
This word is usually used in two senses. In a broad sense, a quasi-experiment is a general way of planning a study in psychology that involves the collection of empirical data, but not all the key stages of the study. In a narrow sense, this is an experiment that is aimed at confirming a certain hypothesis. At the same time, due to various circumstances, the researcher does not sufficiently control the conditions for its implementation. Perhaps that is why a quasi-experiment is sometimes not considered a full-fledged study, the results of which can be trusted and operated on. However, this is completely unfair (although it cannot be denied that some studies using this method were indeed conducted in bad faith).
Big difference
There is a really important difference between an experiment and a quasi-experiment in psychology (the term is mostly used in this scientific field). Usually it goes like this: the scientist does not directly influence the individuals under study, as it should be carried out in a real experiment. For example, if a psychologist wants to study techniques for memorizing poems in kindergarten, then in the case of a quasi-experiment, he will not divide children into groups, but will study already established groups in a team that learn poetry in different ways. Therefore, this process is also called differently - the mixed planning experiment. In addition, there is another name - the ex-post-facto experiment,since data is collected and analyzed after an event has occurred. A variety of groups of people can be studied in this way: victims of violence or disaster, students at school, adopted children or separated twins - that is, groups that cannot be artificially created.
In the experiment, the psychologist will certainly divide the children into new groups and will completely control the learning process. Thus, in both cases, the researcher will come to conclusions, but in the case of a quasi-experiment in psychology, there is a certain risk that these results will be more superficial and, possibly, speculative, depending on the psychologist's position.
Three main types
There are only three kinds of quasi-experiment:
- The case when the researcher does not equalize the study groups.
- No control group required for experiment.
- The impact on the subject is real, not artificially created.
Why are they held?
One should not think that quasi-experiments are the lot of armchair scientists who do not dare to interfere in the surrounding reality. The fact is that many experiments simply cannot be built in laboratory conditions, and only there is a situation of complete control possible. Accordingly, scientists are forced to work in the field with real situations, where the possibility of control is significantly reduced, and sometimes even impossible.
In addition, it is important to conduct a so-called blind or masked experiment, which can also often be equated with a quasi-experiment. Its participants should not know that they are being studied. In this case, the effect of expecting any result from the subjects disappears. For example, if there are two classes, one of which has students in the regular curriculum and the other class has an experimental program, it is important that the children are not aware of this, otherwise the results may differ significantly from the situation of the quasi-experiment. This can manifest itself in many ways, for example, students who are applied to a new program can try very hard.
Also, there are dependencies that cannot be managed. For example, if a researcher is considering how a new law has affected the life of a particular society, it is unlikely that he will be able to control the situation completely.
General logic of the method
In general, the quasi-experiment in its logic (and specifics) does not differ from the usual experiment. In the same way, the stages, the scope are highlighted, and the results are analyzed. Thus, the main feature of the quasi-experiment is that the researcher does not control the process completely, because its possibilities are limited.
However, this does not mean at all that this is a poor-quality method for studying various psychological characteristics of a person. In principle, any real experiment that is not carried out in the laboratory, incan be considered a quasi-experiment to a large extent.