Research Methods

Question 1

Experimental design -
Independent groups

Answer 1

+ no order effects: Pps are only tested once, so can’t practice/ become tired. Controls an important CV
+ Not guess aim: Pps are unlikely to guess the research aims. Behaviour will be more ‘natural’
- Pps variables: Pps in the groups are different, acting as EV/CV. Reduce the validity
- more Pps: Twice as many Pps as repeated for the same data. Expensive and more time spent recruiting

Question 2

Experimental design:
Repeated measures

Answer 2

+ Pp variables: Person in both condition has the same characteristics. Controls the CV
+ fewer Pps: Half the number of Pps needed than independent group. Less time recruiting
- order effects: Pps may do better or worse when doing a similar task twice. Reduces validity of results
- Pps may guess aims: Pps may change their behaviour, reducing the validity of the results.

Question 3

Experimental design:
Matched pairs

Answer 3

+ Pps variables: Pps matched on variables related to the experiment. Enhances the validity and results.
+ no order effect: Pps are only tested once so no practice/ fatigue. Enhances the validity of the results
- Matching is not perfect: is time-consuming and can’t control all relevant variables. May not address Pps variables
- More Pps: Need twice as many Pps as repeated for the same data. More time spent recruiting- expensive.

Question 4

Types of experiments:
Laboratory

Answer 4

+ EV’s and CV’s controlled: the effect of EVs and CVs in the DV can be minimised. Cause and effect of IV and DV can be demonstrated (internal validity)
+ can be replicated: standardised procedure allows the experiment to be repeated. If results are same this conforms to the validity
- lacks generalisability: lab may be rather artificial and Pps are aware they are being studied. Behaviour may not be ‘natural’ and can’t be generalised
- demand characteristics: cues in the situation may invite a particular response from the Pps. The results may be explained by these cues rather than the effect of the IV.

Question 5

Types of experiments:
Field

Answer 5

+ natural environment: Pps more comfortable in their own environment. Results may be more generalisable to everyday.
+ Pps are unaware of being studied: more likely to behave as they normally do. Findings can be more generalised- greater external validity.
- difficult to control CVs: changes in the DV may be form the CVs not the IV. More difficult to establish cause and effect.
- ethical issues: Pps may not have given informed consent. This is an invasion of Pp’s privacy.

Question 6

Types of experiments:
Quasi-experiment

Answer 6

+ high control: carried out under controlled conditions, therefore sharing some strengths with lab experiments. Increased confidence about drawing conclusions
+ Comparison can be made: the IV is a difference between people. Meaning comparisons between different people can be made
- not randomly allocated: Experimenter has no control over which Pps are in which condition as the IV is pre-existing. Pps variables may cause the change in DV.
- casual relationships not demonstrated: Researcher does not manipulate the IV. Cannot say if any change in the DV acting as a CV