Control of variables definitions

Question 1

What are extraneous variables?

Answer 1

Any variable that may have an effect on the DV if it isn’t controlled.

Question 2

What are confounding variables?

Answer 2

Any variable that may have affected the DV and so we don’t know whether the IV changes it or not.

Question 3

What are demand characteristics?

Answer 3

Cues from the researcher or situation which may lead to volounteers changing their behaviour in the experiment.

Question 4

What are Investigator effects?

Answer 4

Anything which the investigator does which affects the DV.

Question 5

What are the two main types of extraneous variables?

Answer 5

Situational variables-outside influences on the experiment such as time of day, wheather, noise etc.
Participant variables-Individual differneeces between participants like age, gender, social class etc.

Question 6

What is standardisation?

Answer 6

Making all instructions and procedures the same to reduce situational variables.

Question 7

What are order effects?

Answer 7

Problems that happen when repeating experiments such as fatigue or boredom which can lead to false results.

Question 8

How can you reduce order effects?

Answer 8

Counterbalancing-Reversing the order of tasks to balance out results
Randomisation-Giving everyone tasks or data assigned randomly.