Experimental Design

Question 1

What is the independant variable?

Answer 1

the variable that is changed/controlled to test the dependent variable

Question 2

What is the dependant variable?

Answer 2

the variable being measured

Question 3

When might a within-participants design not be practical?

Answer 3

In an ageing study (because all participants are involved in both groups it would mean you would have to wait for them to age to conduct pt.2 of the study)

Question 4

3 advantages of a within-participants design?

Answer 4

• manages individual differences
• inc statistical sensitivity
• less participants needed

Question 5

3 disadvantages of within-participants design?

Answer 5

• participants are aware of hypothesis (hawthorn effect)
• need more stimuli
• might be susceptible to ‘order effects’

Question 6

What are order effects?

Answer 6

differences that occur in research due to the order of the participants exposure to the materials etc.

Question 7

Give 3 examples of order effects

Answer 7

• learning
• practice
• boredom/fatigue

Question 8

Name and describe a solution to order effects

Answer 8

Counterbalancing - where research conditions are presented randomly in all permutations (all possible orders)

Question 9

Explain mutual exclusivity

Answer 9

P(A+B)=0 - two things can’t occur at the same time (probability is 0)

Question 10

Give examples of two types of mutually exclusive groups

Answer 10

Gender effects

Psych disorders

Question 11

4 advantages of a between-participants design?

Answer 11

• participants don’t know the hypothesis or the other conditions; lowering demand characteristics
• no order effects
• less stimuli needed
• simple to design

Question 12

2 disadvantages of a between-participants design?

Answer 12

• inc statistical noise (too much variation in results)

- more participants needed

Question 13

Name 2 types of demand characteristics

Answer 13

• hawthorne effect

- placebo effect

Question 14

What are demand characteristics?

Answer 14

participants form an interpretation of the experiment’s purpose and unconsciously change their behavior to fit that interpretation

Question 15

Describe the Hawthorne Effect

Answer 15

the participant observes a change and wants to meet the demand of the experiment, so an effect happens regardless of the variable change

Question 16

How can the hawthorne effect be prevented?

Answer 16

the participants being naive to the hypothesis

Question 17

What are confounds?

Answer 17

uninteresting factors (e.g. social, environmental that weren’t being originally tested) that affect measurements systematically - can create bogus results

Question 18

Give 4 examples of confounds

Answer 18

• time of testing
• gender of experimenter
• room noise level
• before/after a lecture

Question 19

How can confounds be controlled?

Answer 19

By having a control experiment that is similar but not the same as the experiment. Having it double-blind improves also

Question 20

What is a double-blind experiment?

Answer 20

Participants AND experimenter aren’t aware of group they are in/hypothesis etc

Question 21

What can be a solution to deception in studies

Answer 21

Debriefing

Question 22

What is the problem with informed consent?

Answer 22

It may introduce bias

Question 23

What is the social desirability effect?

Answer 23

A response bias that causes respondents to answer in a way that they think will be viewed favourably by others. Causes people to over-report the good and under-report bad