Types of experiments
Ethics of experimentation
What do these threeterms mean?causalityhypothesishypothetico-deductiveapproach
In this chapter, we are looking at the research method known as the experiment. Experiments have rather a special place in psychology, because they are the only research methods which directly explore causality – in other words, because they can allow us to sort out whether something is really causing something else to happen. Other research methods may suggest that something is causing something else, but they can't really tell us for sure that it is.
The problem, though, is that investigating causality isn't that straightforward, particularly when you are trying to investigate causality in human beings or animals. There are all sorts of ways that people (and animals) can be influenced, and also ways in which their own understanding of what is going on influences how they act. So experiments in psychology need to be rather elaborately designed, if they are really going to identify causes.
One of the most important aspects of experiments as a research method is the way that they are always designed to test a hypothesis. Experimental studies generally adopt the hypothetico-deductive approach to research which we looked at in Chapter 1. This means that they aim to investigate a theory – some kind of general explanation for why something happens. The aim of an experiment, ideally, is to gain evidence which will support that theory, or which will challenge it.
So one of the first things we need to do if we are about to conduct an experiment is to sort out the hypotheses which it will be investigating. Any one theory can give rise to several different hypotheses,