Experimental design

A plan for collecting and treating the data of a proposed experiment. It is important that the experimental design provides the opportunity to make appropriate inferences and decisions relating to the hypothesis from the data.

Control group: In an experimental design, which is contrasting two or more groups, the control group of subjects is not given the treatment whose effect is under investigation.

Experimental group: In an experimental design, which is contrasting two or more groups, the experimental group of subjects is given the treatment whose effect is under investigation.

Between subjects design: In a between subjects design the values of the dependent variable for one subject or group of subjects (e.g., the experimental group) are compared with the values for another subject or another group of subjects (e.g., the control group).
Within subjects design: In a within subjects design the values of the dependent variable for an item or a set of items (e.g., the experimental items) are compared with the values for another item or another set of items (e.g., the control items) within one person.
Literature: Atkinson, Atkinson, Smith & Bem (1990), Schmidt (1993)

Entry by: Stefan Schwarz


June 7, 1999
Direct questions and comments to: Glossary master