Sampling Techniques, Generalisation, Bias etc.

Question 1

What are the five sampling techniques?

Answer 1

R.O.V.S.S
Random
Opportunity
Volunteer sampling
Systematic 
Stratified.

Question 2

Random sampling

Answer 2

A sample in which every member of the target population has an equal chance of being selected.

Advantages:
Unbiased.
All members of the target population have an equal chance of selection.

Disadvantages:
Doesn’t guarantee a completely representative sample - One type of participant is selected.

Question 3

Opportunity

Answer 3

A sample that consists of those people available to the researcher.

Advantages:
Easiest method and takes less time.

Disadvantages:
May result in sample being biased - One group may contain the same people.

Question 4

Systematic

Answer 4

A sample where every nth person from a list is selected.

Strengths:
Unbiased sample - therefore more likely to be representative.

Weakness:
May be unrepresentative and it doesn’t guarantee unbiased selection.

Question 5

Stratified

Answer 5

Smaller reproduction of the population. E.g. Gender, Age.

Strengths:
Representative of the population - therefore generalisations can be made.

Weakness:
Complete representation isn’t possible as the identified strata doesn’t reflect all the differences.

Question 6

Volunteer Sampling

Answer 6

Involves participants selecting themselves for the research concerned - often replying to an advertisement.

Advantages:
Relatively easy to conduct participants - therefore less time consuming than other forms of sampling.

Disadvantages:
People who respond may not be typical of the target population - so the sample will not be representative.

Question 7

Bias

Answer 7

Sampling technique may be bias when certain groups are under or over represented.

Question 8

Generalisation

Answer 8

Results can be applied to the population.

Can only happen if the sample is representative.

Question 9

Demand Characteristics

Answer 9

Features a piece of research, which allows the participant to work out its aim and/or hypotheses.
Participants may change their behaviour to frustrate the aim of the research.

‘Please you’ effect = To help the researcher.
‘Screw you’ effect = To Mess up the research for the researcher.

Question 10

Investigator Effects

Answer 10

Occurs when the researcher’s behaviour or characteristics influence the research in some way.