sampling Flashcards
random sampling
every person from target population has an equal chance of being picked for sample
strength of random sampling
- representative sample
- generalisable results
- all members have an equal chance of being chosen
weakness of random sampling
- time consuming
- impractical
systematic sampling
members of target population are selected systematically
weakness of systematic sampling
- periodic traits ( traits shared by every person) can result in unrepresentative results
strength of systematic sampling
- unbiased selection increases chance of achieving representative sample
- generalisable results
stratified sampling
- proportional representation of target population thats being selected
- reflects the proportions of certain sub groups within population e.g age gender
weakness of stratified sampling
- time consuming
- difficult to do as knowledge of population is required
strength of stratified sampling
- representative of population
-unbiased
opportunity sampling
- sampler selects p from whoever is alavaliable at the time
strength of opportunity sampling
convenient
easy and quick
weakness of opportunity sampling
unrepresentative sample, leads to results that aren’t generalisable
volunteer sampling
p put themselves forwards to be in a sample
strength of volunteer sampling
p would be very motivated
easy to do
weakness of volunteer sampling
- un represerative sample as likely to be biased
- demand characteristics
Q: What is an advantage of time sampling?
A: It reduces the number of observations required, making it less time-consuming.
Q: What is time sampling in observational studies?
A: Time sampling is the recording of behavior within a pre-established timeframe during an observational study.
Q: What is a disadvantage of time sampling?
A: The small amount of data collected within the timeframe can be unrepresentative of the overall observation.
Q: What is event sampling in observational studies?
A: Event sampling involves counting the number of times a particular behavior occurs in the target group or individual.
Q: What is an advantage of event sampling?
A: It is useful for recording infrequent behaviors that might be missed with time sampling.
Q: What is a disadvantage of event sampling when observing complex behaviors?
A: Important details of complex behaviors may be overlooked by the observer.
Q: What is a disadvantage of event sampling for frequent behaviors?
A: There could be counting errors, and it can be difficult to judge the beginning and ending of the behavior.
