C. Hypothesis Testing

Why Use Hypotheses in Social Science Research?

In examining phenomena of the social world, there are any number of relationships that we could examine to learn more about their workings. However, it is possible that some of the relationships that we observe might be due to chance, rather than some relationship between two variables.

For instance, consider a hypothetical experiment that is designed to evaluate whether enhancing hospital patients' "sense of control" influences their health. In this experiment, conducted in McGregor Hospital, ten people in the chronic care ward were sampled and given "enhanced control" over their schedule and living conditions. They could specify when they would have their meals, which hours they could receive visitors, and which programs they could watch on television. To compare the benefits of this enhanced control, an additional ten patients of the chronic care ward were chosen, though their routines were not altered.

After six weeks, the health of all subjects was measured and it was found that the mean level of health (on a 10-point scale with higher numbers indicating better health) was 6 for the enhanced control group and 4 for the non-enhanced group.

Perhaps the first question that should be asked is: "Can we be sure that the enhanced sense of control is responsible for the difference between the groups, rather than chance?" It might be that simply by chance the people who were chosen for the enhanced control group were somewhat healthier before the experiment than those assigned to the other group. Or it might be that these differences were due only to chance, rather than some benefit of control over living conditions.

What is needed is a way to evaluate the likelihood that relationships, such as those in the study in the hospital described above, occurred by chance. The establishing and testing of hypotheses is such a method.