Research Methods

Question 1

Random Sample

Answer 1

Every member of the population has an equal chance of selection (list of population,random number generator)

+ Representative Sample
- Difficult to achieve due to large population

Question 2

Stratified Random Sample

Answer 2

Diving population into categories and selecting at random in proportions equivalent to population.

+ Eliminates the effect of the variable on which the sample is stratified
- Time consuming, example

Question 3

Convenience Sample

Answer 3

Picking whoever is available at the time

+ Quick,easy,cheap
- Bias in sample

Question 4

Repeated Measures

Answer 4

Each participant is part of both E and C group

+ Elimination of participant variables, use fewer participants
- Takes long time so drop outs likely.
- Order effects - changes in results caused by the sequence of performing tasks in a test
Counterbalancing - Different conditions be presented in different sequence to different groups of participants.

Question 5

Matched Participants

Answer 5

Researcher is able to identify a variable that is likely to confound and climate the effects of the variable from the experiment.

+ variable on what participants are matched will not influence results
- Time consuming, if one pair drops out, the scores for the other must be eliminated.

Question 6

Independent Groups

Answer 6

Allocates participants to E or C group at random

+ Dropouts unlikely
- Large number of participants required

Question 7

Random Allocation

Answer 7

all participants who have been selected for an experiment must have an equal chance of being in E or C group.