Sampling Flashcards
strengths of random sampling
+ researcher can’t be accused of being biased in their selection of Ps
weaknesses of random sampling
- sample could be unrepresentative
strengths of opportunity sample
+ less time consuming than other sampling methods to locate Ps
weaknesses of opportunity sample
- sample likely to be biased
strengths of systematic sampling
+ if initial P is selected randomly then selection of Ps is unbiased
weaknesses of systematic sampling
- sample could be unrepresentative
strengths of stratified sampling
+ sample will be representative of all relevant subgroups
weaknesses of stratified sampling
- Ps randomly selected from each subgroup may not be representative of that subgroup
strengths of quota sampling
+ representative of all relevant subgroups
weaknesses of quota sampling
- researcher bias
strengths of self-selected sampling
+ the Ps are willing to take part in research
weaknesses of self-selected sampling
- Ps likely to be highly motivated- unrepresentative
strengths of snowball sampling
+ helpful when selecting Ps with unique/rare characteristics
weaknesses of snowball sampling
- initial Ps may not be able to recruit enough Ps
event sampling
observer records number of times a behaviour/event occurs
strengths of event sampling
+ all behaviours/events that occur are recorded
weaknesses of event sampling
- we don’t know if there’s a change in behaviours/events that occur over time
- may get overwhelmed with data
time interval
observer records number of times a behaviour/event occurs in specified intervals of time
strengths of time interval
+ allows to see if there’s a change in behaviours/events that occur over time
weaknesses of time interval
- may get overwhelmed with data
time point
observer records the behaviour/event that’s occurring at specific point in time
strengths of time point
+ allows to see if there’s a change in behaviours/events that occur over time
+ won’t get overwhelmed with data
weaknesses of time point
- if behaviours/events don’t occur at the specified point in time- they won’t be recorded
repeated measures
same Ps in both conditions
strengths of repeated measures
+ there’s no chance of intergroup differences as all Ps take part in all conditions
+ needs fewer Ps than IG or MP
weaknesses of repeated measures
- more chance of demand characteristics- Ps taking part in both conditions
- order effects may occur e.g: practice and fatigue
independent groups
different Ps in both conditions
strengths of independent groups
+ no order effects- Ps only take part in 1 condition
+ less chance of demand characteristics- Ps only take part in 1 condition
weaknesses of independent groups
- may be unknown intergroup differences that are responsible for any difference in DV
- needs 2x as many Ps as a RM design
matched pairs
similar Ps in both conditions- Ps matched up into pairs and randomly allocated to a condition
strengths of matched pairs
+ no order effects- Ps only take part in 1 condition
+ less chance of demand characteristics- Ps only take part in 1 condition
weaknesses of matched pairs
- needs 2x as many Ps as RM design
- uncontrolled intergroup differences that’s responsible for any differences in DV
