experimental designs counterbalancing

Question 1

what are the three experimental designs?

Answer 1

repeated measures design
independent groups design
matched pair design

Question 2

describe the repeated measure design

Answer 2

the same participants take part in both conditions (e.g noisy and silent)
condition one-the group takes part in the first experimental task with the IV set for condition one.
condition two-the group repeats the experiment with the IV set for condition two.

Question 3

describe the independent group’s design

Answer 3

Participants are randomly allocated to either one or the other condition (e.g noisy and silent)
one group takes part in one condition and the other in the other condition then results are compared for each

Question 4

describe the matched pair design

Answer 4

participants are matched closely as possible with another participant- the pairs are randomly allocated to either one or the other condition (e.g noisy or silent)
the results for either condition are then compared.

Question 5

what are some strengths and weaknesses of the repeated measures design?

Answer 5

+fewer participants are needed

• order effects such as fatigue and boredom affect the results but can be controlled through counterbalancing
• increased chance of demand characteristics.

Question 6

what are some strengths and weaknesses of the independent group’s design?

Answer 6

+participants are randomly allocated to either condition; reduced bias

• more participants needed
• least effective design for controlling participant variables

Question 7

what are some strengths and weaknesses of the matched pair design?

Answer 7

+participants are matched as closely as possible with another participant- then are randomly allocated
+participant variables are eliminated however it’s not possible to match all the participant’s characteristics.
-requires more participants and is time-consuming

Question 8

what are order effects?

Answer 8

In repeated measures design, an extraneous variable can arise from the order in which conditions are presented e.g fatigue and boredom effects.

Question 9

what is counterbalancing?

Answer 9

an experimental technique used to overcome order effects when using a repeated measure design. Counterbalancing ensures that each condition is tested first or second in equal amounts.

Question 10

what is an example of counterbalancing?

Answer 10

AB or BA
participants are split into two groups, both of which test both conditions. one group carry out condition A then B and the other group carried out condition B then A.
This allows for comparison of each participants performance on both conditions.
This also reduces the impact of order effects as they are balanced out.