Research Methods : Experimental Designs Flashcards
experimetnal design
how pt arranged
in relation to
investigating different experimental conditions
independent group design
2/ separate groups of pt
experience diff conditions
within the experiment
in independednt group if two levels of IV how many IV do pt experience
1
what is compared between the two groups in independent group design
performance
what is a repeated measure design
all particpants experiecne both conditions of the experiment
give e.g of how REPEATED MEASURES DESIGN would work - read the group design im asking for !
all partipants try condition a then allpt try condition b
what is compared in repeated measures and why
means of conditions
to see if theres difference
what os amtched pair design
pt paired based on variables relevant to experiment and then spit into different experimental conditions e.g iq
explain how pt matched together in memory study on the basis of IQ
matched on iqs as indicator of ability to recall info
top 2 iqs paired together
then perosn 1 experiences condition a
person 2 experiences confiiton b
and so on
what do matched pairs attempt to control
confounding variable of pt variables
what does a matched pair require if it is to be effective
pretest if matching is to be effective
how could you select matched pairs when observing hwo chattiness affected by coke
observe two chattiest people in the waiting room
its key : in an experiment the matched pair after being selected is then ran how ?
in same way as independent groups
-ve/biggest issue of a pt group (pv)
pt who … the … groups are not the … in terms of …. variables
Pt who OCCUPY the DIFFERENT groups are not the SAME in terms of PARTICIPANT variables
exaplin the biggest issue of IGD (PV)
biggest issue with independent group design is participants who occupy the different groups are not the …. in terms of ….
so if researcher finds a …. between the groups on the …. ….
this may be more to do with … .. than the effects of the …
therefore these differences may act as a … … reducing the …. of the …
biggest issue with IGD is pt who occupy the different groups are not the SAME in terms of PT VARIABLES
so if researcher finds A DIFFERENCE between group on the DV this may be more to do with the PV instead of effects of the IV
therfore these differences may act as a CONFOUNDING VARIABLE
reducing the VALIDITY of the FINDINGS
how can you deal with pt in diffreent groups not being equal in terms of PT variables
random allocation
Random Allocation
evenly …. the pt ….
across …. of the experiment
using … techniques
evenly distributing pt characteristics
across conditions of experiment
using random techniques
give an example of random allocation
paper with A/B written on them
placed in hat
researcher selects them one at a time to assign pt to groups
r -ve of independent group design (Point about RMD)
less economical than repeated measures
explain why IGD less economical than repeated measures
each pt contributes a .. .. only
therfore … times as many participants are …. to produce …. …. to that collected in a … … …
this therefore increases …. and … spent on recruiting pt
pt contributes SINGLE RESULT
2x many needed produce EQUIVALENT DATA that collected in RMD
therefore increases TIME/MONEY spent on recruting pt
+ves of IGD (0rder effect) short
prevents … ….
which is a problem in .. .. ..
as only … … condition
pt are … likely to … the aim which reduces …. ….
prevents order effect - a problem in RM
as only experience ONE condition
pt less likely to guess the aims which reduces DEMAND CHARACTERSITICS
biggest issue for RMD
order effects
eahc pt min 2 tasks
order of tasks may be significant
give e.g of when order effects happen in RMD
drinking coke in our chatty patty experiment
drinking coke may have continuing effects when drinking water
how do you deal with order efffects
counterbalancing
