Sampling Flashcards
what is opportunity sampling?
paprticiaptns happen to be available at the time.
What are the strengths to opportunity sampling?
easy method to recruit which saves time and money.
What are the limitations of Opportunity sampling?
- Not representative to the whole population. 2. Researcher bias is presented as they control who they want to select.
What is random sampling?
when all of the members of the population have the same chance of being selected.
What are the advantages to random sampling?
No researcher bias.
What are the disadvantages of random sampling?
Time consuming to pick, volunteer bias when they refuse to take part so could be unrepresentative.
What is systematic sampling?
Used whereby every nth member is selected from the sampling frame.
What are the advantages to systematic sampling?
Avoids researcher bias and usually fairly representative.
What are the disadvantages to systematic sampling?
Not truly unbiased.
What is stratified sampling?
The composition of the sample reflects the varying proportions of people in particular subgroups within the wider population.
What are the advantages to stratified sampling?
- No researcher bias.
- Produces Representative data due to the proportional strata.
What are the disadvantages of stratified sampling?
- Time consuming.
- A complete representation of the target population is not possible as the identified strata cannot reflect all the differences between the people of the wider population.
What is volunteer sampling?
Involves self selection whereby the participant offers to take part either in response to an advert or when asked to.
What are the advantages to volunteer sampling?
- Quick access to ppts therefore is easy and not time consuming.
- As people volunteered they are more likely to take part in the study.
What are the disadvantages to volunteer sampling?
- May attract a certain type of person - volunteer bias.
- Motivation like money could lead to ppts not taking things seriously.
