Of course, there are many different ways of testing the research hypotheses.
Although this is an oversimplification, the following three general research methods may be distinguished:
- surveys/non-experiments; and
This is not a complete list by any means. However, it does include most of the research methods likely to be used by beginning researchers.
It is difficult to imagine psychology without experiments. The experimental method is so common in psychological research that it is almost a defining characteristic of the discipline.
The use of experiments in psychology reflects the intellectual origins of psychology in disciplines such as physics and biology in which experiments were commonplace.
Experiments involve intervening in a situation in order to see whether this intervention changes things.
The following should provide enough information for immediate purposes.
- Experiments in psychology are almost always controlled experiments. This means that at a minimum they involve an experimental group and a control group which are treated differently. Differences in the way in which the two or more groups are treated may influence differentially measurements of a particular variable.
- No other research method in psychology is able to explore causal relationships between two variables as effectively as the best experiments can. A causal relationship is merely one in which a particular variable influences another variable. In the real world outside the psychological experimentitis often very difficult to say whether a relationship between two variables is causal or not.
For example, if parents treat their daughters differently from their sons we cannot say whether this difference is because of the behaviour of the parents or the behaviour of the children. Boys may differ from girls and it may be this difference which influences the behaviour of their parents rather than the behaviour of the parents causing the differences between the boys and girls.
Daughters and sons may behave differently which causes their parents to behave differently towards them.
- A cause-and-effect relationship is another way of saying causal relationship. It merely means that one variable is causing an effect on the another variable. The variable doing the causing is called the independent variable and the variable being affected is called the dependent variable.
- Many psychologists believe that the most appropriate method for determining causality is the experiment. On the other hand, many others suggest that for some kinds of research experiments result in trivial and confusing findings.
• Randomisation is crucial in experiments. The term refers to an unbiased way of allocating individuals to the experimental and control conditions. Tossing a coin is one possible random procedure for allocating participants into the experimental and control conditions.
If the coin lands heads then we would allocate the next participant to the experimental group, if tails to the control group. Without random allocation one cannot be certain that the people in the experimental group are similar to those in the control group on some pre-existing basis.
- Because it is essential to standardise procedures, experiments sometimes appear more contrived than other forms of research. However, every research method has its limitation and different methods have different limitations as will be seen.
- An example of an experiment may involve testing the hypothesis that sexual arousal increases feelings of love for one’s partner. We could randomly assign people with partners to one of two conditions. In one condition, people would read a sexually exciting passage from a magazine before rating how much they loved their partner while in the other condition they would read a passage which was not sexually exciting.
A sufficiently large difference in the average rating in the two different conditions would reflect the causal influence of sexual arousal on feelings of love.