Experimental design

Question 1

define experimental design

Answer 1

The different ways in which the testing of participants can be organised in relation to the experimental conditions.

Question 2

what are the types of experimental designs

Answer 2

• independant groups/ measures
• repeated groups/ measures
• matched pairs design

Question 3

define independent groups design

Answer 3

consists of using different participant for each condition of the experiment.

If two groups consist of different individuals then this is an independent measures design.

Question 4

what are the advantages of using independent measures

Answer 4

• order effects dont exist since the participant only does one condition
• Demand characteristics are less of a problem as the participant only sees one condition so are naive to the test.
• the same test can be used

Question 5

What are the disadvantages of independent measures

Answer 5

• individual differences may affect the results
• more subjects are required so it is less economical.

Question 6

define repeated measures design

Answer 6

involves using the same participants in each condition of the experiment

Question 7

what are the advantages of of repeated measures

Answer 7

• individual differences are kept constant in the conditions
• fewer subjects are required so is therefore more economical

Question 8

what are the disadvantages of repeated measures

Answer 8

• order effects can become a fact due to practice
• demand characteristics may become a factor as the subject does both conditions so may guess the aim of the study and act differently.
• different tests may be needed

Question 9

define matched pairs design

Answer 9

is an experimental design where pairs of participants are matched in terms of key variables, such as age and IQ

Question 10

what are the advantages of matched pairs design

Answer 10

• participant variables are kept more constant
• order effects dont occur
• demand characteristics are less of a problem as they do one condition so are unlikely to geuss the experiment
• the same test can be used

Question 11

what are disadvantages of matched pairs design

Answer 11

• participant variables can never be a perfect match
• matching subjects can be very time consuming and difficult
• more subjects are required so it is less economical.

Question 12

list some order effects

Answer 12

• learning
• fatigue
• boredom