The hypothesis that is accepted if the null hypothesis is rejected, usually represented by the symbol H1. Also known as the experimental or research hypothesis. The alternative hypothesis usually stat [..]

A sample based on subjects who are available and willing to participate in the study. Many experiments in psychology use undergraduates as subjects as they are cheap and easy to find.

An experimental design in which each subjects is randomly assigned to only one of the treatment conditions.

A research method involving the detailed study of a single individual, used mainly in clinical psychology and neuropsychology.

The appropriate test to investigate independent frequency counts taken from a sample.

An independent variable created by the selection of subjects on the basis of a factor such as age or gender. It is a characteristic which is observed and classified rather than imposed by the experime [..]

One or more variables not under the control of the experimenter that vary systematically with the independent variable, decreasing the experimenter's ability to isolate cause and effect.

A group of subjects which does not receive the experimental treatment but in all other respects is treated in the same way as the experimental group, (so as to tease out the effects of the treatment i [..]

A statistical relationship between two variables such that high scores on one factor tend to go with high scores on the other factor (positive correlation) or that high scores on one factor go with lo [..]

A type of research design in which patterns of correlations are analysed.