Which design compares two separate groups: experimental vs control?

Which design compares two separate groups: experimental vs control?

• A. Independent Samples Design
• B. Repeated measures design
• C. Matched pairs
• D. Small n design

Answer: (A)

When you compare an experimental group to a control group, you assign different participants to each group so the groups are independent. This setup is called an independent samples design, or between-subjects design. The crucial idea is that each participant experiences only one level of the independent variable, so any differences between the groups reflect the effect of the manipulation rather than differences within participants. This contrasts with designs where the same people undergo every condition (repeated measures), which creates non-independent data and two not-quite-separate groups. A matched pairs approach forms two groups by pairing individuals on certain characteristics and then assigning each member of a pair to a different condition; while it still compares two groups, the matching introduces a specific relationship between them rather than purely independent groups. A small-n design involves studying a very small number of participants and isn’t about comparing two separate groups in the between-subjects sense.

When you compare an experimental group to a control group, you assign different participants to each group so the groups are independent. This setup is called an independent samples design, or between-subjects design. The crucial idea is that each participant experiences only one level of the independent variable, so any differences between the groups reflect the effect of the manipulation rather than differences within participants.

This contrasts with designs where the same people undergo every condition (repeated measures), which creates non-independent data and two not-quite-separate groups. A matched pairs approach forms two groups by pairing individuals on certain characteristics and then assigning each member of a pair to a different condition; while it still compares two groups, the matching introduces a specific relationship between them rather than purely independent groups. A small-n design involves studying a very small number of participants and isn’t about comparing two separate groups in the between-subjects sense.