Lab Experiments

Question 1

What is a limitation of experimental manipulation?

Answer 1

The difference between the IV and the DV aren’t always as a result of the manipulation. Maybe they have affected the participants but not in the expected way as a result of confounding or extraneous variables.
e.g. anger study, researcher states offensive comments to ps, some ps may get angry, others may find the insults funny

Question 2

What is an automated procedure?

Answer 2

No researcher present at the time of the study, pre-recorded audio instructions are given by loudspeakers to the ps, ensures all ps hear identical instructions

Question 3

What aren’t so obvious examples of variables that need to be standardised?

Answer 3

Weight of a person
Time of day
When they last ate

Question 4

What is a limitation of the standardised procedure?

Answer 4

Difficult to standardise all aspects of the experiment, so sometimes you should randomise the running of the experimental and control groups, means there’s no systematic bias

Question 5

What are the 2 types of randomised experiments?

Answer 5

1. Ps takes part in only one condition, whether they are put into a control or experimental design is randomised
2. Ps takes part in both conditions, but the order in which they take part in the conditions is randomised

Question 6

What is a limitation of randomisation? How do you combat this?

Answer 6

Despite randomisation, maybe you’re still testing one condition more than the other, sometimes there are unequal numbers of people in both conditions
Combat this by using matched pairs design

Question 7

What is a matched pairs design?

Answer 7

Only match ps based on the variables which are related to the IV and DV
Match people in the sample based on similar variables e.g. weight, height
We could choose one of these ps at random to go into the experimental design and the other to be in the control group

Question 8

What are lab experiments?

Answer 8

IV are isolated
Controlled settings
Establish causality

Question 9

When are naturalistic observations useful?

Answer 9

For social processes: in observations
For correlational studies: uses quasi-independent variables, or where the manipulation of variables is unethical

Question 10

What are the 3 components of lab experiments?

Answer 10

Experimental manipulation
Standardisation
Random Assignment

Question 11

What is experimental manipulation?

Answer 11

Researchers can control and manipulate the true IV
Quasi experimenter variables can be in lab experiments, but aren’t under full experimenter control, causality is harder to establish
Operationalise variables
Manipulation check: assess whether the manipulation worked
Pilot study

Question 12

What is a pilot study?

Answer 12

Small scale experiment to check the IV works as intended and the experimental design is tolerated by participants as well
Questionnaires or debriefs: ask ps their opinion about the study, or use established measures you know are affected by the IV

Question 13

What is the standardisation of procedures?

Answer 13

Apart from the baring differences between conditions, ps should experience the experiment in the same way
Experimental control: control for extraneous and confounding variables

Question 14

What is randomised assignment?

Answer 14

Randomly allocated into conditions
Different ways of doing this: coin flip, selected out of a hat
Make sure ps have an equal chance of ending up in either condition

Question 15

What is a between subjects design?

Answer 15

Complete only one condition
Random allocation into each condition

Question 16

What is a within subjects design?

Answer 16

Ps complete all conditions
Counterbalance: random allocation to the order of the conditions. A/B or B/A

Question 17

What are the strengths/weaknesses of a between subjects design? What’s a solution?

Answer 17

+ ps are unaware of the differences between conditions
+ no order effects
- different groups have different characteristics, these are extraneous variables

This can be controlled through random assignment
Can also be controlled through a pre-post test design

Question 18

What’s a Pre-Post test design?

Answer 18

Pre: if the different groups of ps perform a task before the experimental manipulation
Post: check if the experimental manipulation has changed performance

Question 19

What’s the advantages/disadvantages of a Pre-post test design? What are the solutions?

Answer 19

+ allows us to check if the randomisation has worked
+ allows us to isolate the effect of the IV on the DV
- Can alert the ps to the thing we are interested in, and affect their behaviour
- Can only test the difference in performance from pre to post rather than absolute performance

Solutions:
Disguise the pre test within another task or context.
Increase the time between the pre and post test.
Design your study to include groups without the pre test

Question 20

What’s the weaknesses/strengths of a within subjects design?

Answer 20

+ No chance of differences in groups between conditions
+ Control for individual differences
+ Fewer ps needed overall
- Practise effects
- Boredom
- Carry over-effects