Experimental Designs

Question 1

Independent Groups

Answer 1

A group will do only one of the study’s conditions. A separate group will do the other condition

Question 2

Matched Pairs

Answer 2

Ppts. are paired with another ppt. based on some form of matched variable. The one member of the PIR does one condition and one does the other.

Question 3

Repeated Measures

Answer 3

Each ppt. takes part in every condition being tested

Question 4

Independent Groups eval.

Answer 4

Pros
Avoids order effect (better on 2nd test because of experience)
Avoids ppts. guessing aims of the experiment

Cons
No control of ppt. variables
Need more ppts. than repeated measures

Question 5

Matched Pairs eval.

Answer 5

Pros
Controls for ppt. variables
Avoids order effects

Cons
Time consuming to match ppts. on variables
Can only match on variables we know, others may have an effect

Question 6

Repeated Measures eval.

Answer 6

Pros
Good control of ppt. variables
Fewer ppts. needed than independent groups

Cons
Order effects
Ppts. can guess aims of experiment