experimental design Flashcards
1
Q
what is independent groups design
A
2 sep groups of ppt experience 2 diff conditions
(so if theres 2 levels of the IV then each group experiences one condition only)
2
Q
weaknesses of independent groups design
A
- ppt variables, if more ppt w a particular characteristc are randomly assigned to one group any measures of dv could be due to this and not the IV
- may act as a confounding variable red valdiity (is reduced by random allocation)
- less economical than repeated measures as each ppt = to a single result so would need 2x as many ppt to equal to rep measures (increased time and money)
3
Q
strength of independent groups design
A
- no order effects unlike in repeated measures
- less likely to guess the research aim and act according to demand characteristics bc only take part in one level of the IV
4
Q
repeated measures
A
the same ppt complete all condtions
5
Q
weakness of repeated measures
A
- order effects, taking part in first condition could make performance better in second or worsen due to fatigue or boredom
- ppt more likely to figure out the aim and alter behaviour due to demand characteristcs
6
Q
A
7
Q
strengths of repeated measures
A
- needs half the amount of ppt compared to independent groups for the same amount of data
8
Q
matched pairs
A
ppt are matched on a variable eg IQ and each ppt from a pair allocated a different level of the OV
9
Q
strength of matched pairs
A
-reduced ppt variables as ppt matched on certain characteristic
- no order effects as ppt only take part in one condition
10
Q
weakness of matched pairs
A
- cannot completly limit ppt variables effect on DV
(no one is completly identical even MZ twins) - time consuming to set up and expensive bc need 2x as many ppt to match a rep measures design
