Research Methods - Experimental Design

Question 1

What is experimental design?

Answer 1

Refers to the way participants are used in experiments.

How the testing of participants is arranged in relation to the experimental conditions.

Question 2

What’s independent groups?

Answer 2

Allocation to conditions - Participants are allocated to different groups where each group experiences one level of the IV only.
(If there are two levels to the IV, two groups will be used)

Question 3

Strength of independent groups

Answer 3

• Order effects aren’t a problem, can give same test to both groups
• Participants are less likely to guess the aims

Question 4

Weakness of independent groups

Answer 4

• You need twice as many participants

- The two groups aren’t the same so results could be from participant variables not the IV

Question 5

How to deal with weaknesses for independent groups

Answer 5

Random allocation - theoretically distributes participant variables evenly & is an unbiased method

Question 6

What’s repeated measures?

Answer 6

All participants experience both conditions

Question 7

Strength of repeated measures

Answer 7

• Participant variables are controlled

- Fewer participants needed

Question 8

Weakness of repeated measures

Answer 8

• Order effects are a problem as the order they complete the two tasks may be significant
• May guess aims

Question 9

How to deal with weaknesses for repeated measures

Answer 9

Counterbalancing - half the participants experience the conditions in one order and other half in opposite order
Single Blind Procedure - cover story about purpose

Question 10

What’s matched pairs?

Answer 10

Participants are paired depending on a variable (eg- IQ) & each pair would be split and allocated to a different conditions

Question 11

Strength of matched pairs

Answer 11

• Participants only take part in a single condition so order effects aren’t a problem

Question 12

Weakness of matched pairs

Answer 12

• Can’t be matched exactly so could still be important differences that may effect the DV
• Matching can be expensive and time consuming

Question 13

How to deal with weaknesses for matched pairs

Answer 13

Conduct a pilot study to consider key variables

Question 14

What’s a control group?

Answer 14

A groups of participants who receive no ‘treatment’

Their behaviour acts as a baseline against which the effect of the IV may be measured

Question 15

What’s a control condition?

Answer 15

The condition that provides a baseline measure of behaviour without the IV