Control of Variables

Question 1

Extraneuous Variables

Answer 1

Variables other than the IV that have an effect on the DV and does not vary systematically with the IV - nuisance variables
* should be removed from experiment/well controlled

Question 2

Examples of Extraneuous variables

Answer 2

• Lighting/temp in the lab
• Age of pps

Question 3

Confounding variables

Answer 3

Variables other than the IV which has an effect on the DV - change systematically with the IV
* Difficult for researcher to be sure the origin of the impact of the DV
* CV - could have been the cause instead of the IV

Question 4

Examples of Confounding variables

Answer 4

• Sleep study (investigating relationship between lack of sleep + memory performance) - Completing a memory test later in the day = more tired so do worse
• Remove - pps take test same time of day

Question 5

Demand characteristics