research methods Flashcards
dv
vaiable which is measured
iv
altered to see effect on dv
extranous variables
any other variables which may have an effect on the DV
extranous variables
identfied before the experiment
confouding variables
any extranous variables that afre not controlledd become confounding variables
identfiied after the experiment
partipant varibles
age, past experinecs
sitaution variables
weather, climate etc
experimenter variables
appearance and body langauge, body distractions
control
other then the indepednent varibale, all other variables are held constant so chnage in the DV can only be caused by the mainputlation/change of the IV
randomisation
partcipants are randomly allocated to different conditions of the IV
e.g flipping a coin
extranous variables are liekly to affect one gorup like they are another gorup
little or no effect on DV
other things may be randomised too e.g the order of the events
standardisation
all partcipants have exact same experinece
instructions need to be standardised (same every time)
procedure needs to be standardiesed (same every time)
effects all pariciapnt in all condiitons equally
what ar e the ifferent types of experiments
LAB
QUASI
NATURAL
FIELD
lab experinent
high control over variables
done in lab setting
researcher can manipulate IV to see effect on DV
controlled enviroment
adv of lab experiments
easy replicable
method more objective
easy to establish cause and effect
ROC
dis of lab studies
low ecological validity
pps may conform to demand characteristics
field experiment
more natural environment then lab study
can still manipulate IV t change in DV
ntural enviroment
adv of field experiment
highe cological validity
no demand characterstics
Iv is still manipulated
dis of field experiment
not easily replicable
experimenter cannot control extranous variables
natural experiment
natural environment
experimenter cannot manipulate IV
natural enviroment
adv of natural experiment
high ecological validity
no demand characteristics
dis of natural expeirment
cannot infer cause and effect
cant control extraneous variables
quasi experiment
IV and DV are naturally occurring
can be measured in field or lab
controlled enviroment
adv of quasi experiment
easily replicable
cannot be randomly allocated
dis of quasi experminet
harder to establish cause and effect
aim
precise statemtn of why a study is taking place
hypothesis
more precise statement that predicts what expected to happen
experimental hypotheiss -prediction of what will happen when using experimental method
null hypotheis-states IV will have NO EFFECT on DV
Two types of experimental methods:
directional-states direction of variables (one tailed)
specific
non-directional-does not state the direction of the variables (two tailed)
less specific
when is non diretional hypotehsis used
when no past research
or past research is inconsistent
operationalisable
beig abale to define varibales variables simplu and easily in order to maniupulte IV and measure DV
what are the experimental designs
Repeated measures -lab
Independent groups-field
Matched pairs -natural/quasi
repeated measures
all participants take part in all conditions of the experiment
adv of repeated measures
particpant varibale is controlled
(high validity)
fewer particiapnats needed so less time recruting them
dis of repeated measures
each partcipants has to do at least two tasks
indepedent measures
partcipants allocated t different gorups ]
each gorup represents one condition
adv of independent measures
less leikly to guess aims
order of effects less of an issue
dis of indepednent measures
less economical
matched pairs
natural/quasi
where partcipants are matched in pairs in terms of key variabes e.g age
one is the placed in control group
one placed in experimental group
adv of matched pairs
only taken to one condition so demand charctersics and order of effects less of a problem
dis of macthed pairs
time consuming
less economical
may be expensive
counterbalacning
way of reducing order of effects
one half do the condition
oter half do same condiion second
randomisation
randomsiing the order of trials
randomyl assigned whether do one condion first or second
validity
measure of accuracy
relaibility
measure of consistency
what is the way to test internal reliability
split half method
items are split in half
scores are then both compared
if scores similar, reliable
test external valdiity
test-re-test method
test it one time, test again and compare
if similar, high ecological valiiry
different sampiling techniques
random
systematuc
stratified
opportunity
ROSS
random sampiling
every member of target popualtion has same chnace of being chosen for the sample
e.g pulling names out of hat
adv of random sampiling
free from researcher bias-researchers cant impact
dis of random sampiling
diffcualt to obtain
can still lack popualtion vaility-not generlaisabke to wider popualtion only using target popualtion
systematic sampiling
list of traget popualtion
member is paicked every nth term e.g 3rd or 4th member
adv of systematic sampiling
free from researcher bias
dis of systematic sampiling
may not be represnative of wider popualtion
startified sampiling
list of each vaiable which may have effect on DV is made
work out percentage of each variable in population
adv of stratified sampiling
produces representative sample
dis of startified samppling
time consuming
opportunity sampiling
anyone willign to or wanting to take part
adv of opportunity sampling
cheap
easy to obtain
dis of opportunity sampling
tend to get similar people in similar places
not generalizable to wider population
volunteer sampiling
particopants chose themselves
popele who volunteer to take place
adv of volunteer sampling
easy to obtain
easy to do
dis of volunteer sampling
focuses on same people-lacks popualtion validity
single blind
where the participants do not know under which condition they are being tested
aim-to overcome demand carcterstics
double bind
both particpants and the experimenter do not know the conditions in which the partciants are tested under
aim-to overcome researcher bias/demand characteristics
matched pairs design
partipcnats are matched due to relavet chacrterstics
then allocated to different conditions
aim-recue participant variable/order of effects/demand characteristics
types of observations
NATURALISTIC
PARTCIPANT
CONTROLLED
NON-PARTICIPANT
OVERT
COVERT
NPCnoc
naturalistic
naturally occurring behaviour
adv of naturalistic
high ecological validity
