Experimental Design & Pilot Studies

Question 1

What is experimental design?

Answer 1

The different ways in which the testing of p’s can be organised in relation to the experimental design

Question 2

Independent groups design

Answer 2

• when 2 separate groups of p’s experience 2 different conditions of the experiment
• if there are 2 levels of the IV, all p’s experience only one level of the IV
• p’s randomly selected into each condition to ensure there is no bias

Question 3

Independent groups strengths

Answer 3

• no order effects
• no demand characteristics (only doing one condition=can’t guess outcome of study)
• saves time

Question 4

Independent groups weaknesses

Answer 4

• more p’s needed
• no control over participant variables, can be minimised by random allocation

Question 5

Repeated measure design

Answer 5

• same p’s take part in each condition of the experiment
• 2 sets of data would then be compare to see if there was a difference

Question 6

Repeated measures strengths

Answer 6

• no participant variables as same people are used
• fewer p’s, not as time consuming

Question 7

Repeated measures weaknesses

Answer 7

• order effects, p’s may do worse in the 2nd condition due to boredom/fatigue (can be helped through counterbalancing)
• demand characteristics

Question 8

What is counterbalancing?

Answer 8

Where half the p’s take part in condition a then b and the other half take part in b then a

Question 9

Matched pairs design

Answer 9

• p’s paired together on a variable that is relevant to the experiment
• one member of each pair is randomly placed in the experiment group and the other in the control group

Question 10

Matched pairs strengths

Answer 10

• no order effects
• no demand characteristics
• less chance of participant variables

Question 11

Matched pairs weaknesses

Answer 11

• more p’s needed
• time consuming
• matching is difficult, difficult to know which variables are appropriate

Question 12

What are pilot studies?

Answer 12

• small scale trial runs of an investigation before the real investigation is conducted
• aim is to check the procedure works and allows the researcher to make changes if necessary
• can find issues with experimental design, instructions and measuring instruments
• ensures time & money aren’t wasted on flawed methodology