Sampling methods Flashcards
(15 cards)
What is volunteer sampling?
Self-selected sampling where the participants volunteer to be involved, typically by responding to an advert or flyer.
Why is it a strength that volunteer sampling is convenient with no bias.
This is less time consuming as the participant chooses to take part themselves.
Why is it a strength that there is consent in volunteer sampling?
The researcher is following the code of conduct and know the participant wants to be involved.
Why is it a weakness that there is bias in where flyers, etc, are placed?
The participants who volunteer may have shared characteristics and not be fully generalisable to the target population.
What is Random Sampling?
every member of the target population has an equal chance of being chosen to take part in a study.
How is random sampling done?
identifying the target population and numbering them and selecting the number of participants, then using a random number generator to select them
Why is it a strength that random sampling is unbiased and representative?
Results can be generalised to a wider population.
Why is random sampling difficult to do when there is a large population?
needing to identify everyone’s names, time consuming and maybe not representative.
What is opportunity sampling?
taking the sample from people who are available at the time if they fit the criteria.
e.g., asking people in a library
Why is it a strength that opportunity sampling is quick?
convenient and less time consuming
Why is it a weakness that opportunity sampling is that it’s not representative of the target population?
results are less generalisable due to shared characteristics.
what is stratified sampling?
classifying the population into categories and choosing a sample which consists of participants from each category in the same proportions of the population
e.g., if the population is 60/40 women to men, we would get 600 women and 400 men.
why is it a strength that stratified sampling is representative of a wider population?
Findings can be generalised to the wider population
Why is it a weakness that stratified sampling takes time to calculate the specific numbers needed?
This is time consuming
why is it a weakness that stratified sampling may overlook certain groups?
There may be bias in the sample and lack generalisability.
