Sampling Flashcards
A sample
When we carry out research, we need people to take part,these are called participants
Population
The population is the group of people from whom a sample is drawn. We use a target population if we want to investigate specific individual differences.
Where are people chosen in a random sample
A computer random generator
Are picked out of a hat
Volunteer sampling
Researcher advertises the study, and people who are interested apply to be in the research
Random sample disadvantages
- Researcher may end up with biased sample - sample too small
- Subgeoups of target population might not be selected - doesn’t guarantee a representative sample
Stratified sample
Sample reflects the proportion of people in certain sub-groups(strata), within the target population or wider population
Volunteer sampling advantages
- Quick, convenient and ethical if it leads to informed consent
- Large response rate
- Allows more in-depth analysis and accurate results
Weaknesses of volunteer sampling
Sample is biased, because the participants are likely to be more highly motivated(volunteer bias)
Opportunity sampling advantages
The easiest and fastest methods, because you just use the first participants you can find
Opportunity sampling disadvantages
Biased - sample drawn from a small part of the target population
Unlikely to be representative of a target population
Systematic sampling advantages
It avoids bias, as once the researcher’s decided what number, they have no control over who’s being selected
Systematic sampling weaknesses
Not completely objective - the researcher may decide on how people are listed before the selection
There’s a small chance of a ‘freak’ sample, which would not be representative
Stratified sampling weaknesses
Time-consuming
Small sample - some grojps within a sample may not be represented
