Control of Variables

Question 1

Extraneous variable:

Answer 1

Any variable, other than the IV that may have an effect on the DV if its is not controlled. EVs are nuisance variables that do not vary systematically with the IV.

Question 2

Confounding variables:

Answer 2

Any variables, other than the IV that may have affected the DV so we cannot be sure of the true source of changes to the DV. They vary systematically with the IV.

Question 3

Demand characteristics:

Answer 3

Any cue from the researcher or from the research situation that may be interpreted by participants as revealing the purpose of the investigation. Pps may change their behaviour within the researcher.

Question 4

Investigator effects:

Answer 4

Any effect of the investigator’s behaviour on the research outcome. This may include everything from the design of the study and interaction with participants.

Question 5

Randomisation:

Answer 5

The use of chance in order to control for the effects of bias when designing materials and deciding the order of conditions.

Question 6

Standardisation:

Answer 6

Using exactly the same formalised procedures and instructions for all participants in a research study.