u2 rm1 controlling variables

what is a participant variable

anything that can affect the DV; e.g age, iq

how to control participant variables

repeated measures -> effects of participant variables will be same in both conditions so same effect on dv so they will be cancelled out

Matched pairs -> participant should be controlled

Independent groups -> random allocation

what is a situational variable

anything about the circumstances of the experiment e.g. weather, time of day

how to control situational variables

standardisation -> keep all the conditions and variables same so that effects can cancel out or randomise

what are experimenter effects

aspects of the person conducting research that can affect result

examples of experimenter effects

Expectancy -> beliefs about participant will influence result

Investigator fudging -> lying about results

change responses to present yourself in a favourable light

how to control experimenter effects

double blind procedure

reassure that they aren't judged

Do it anonymously

Specify study so that other researchers can replicate result

what are order effects

repeated measures e.g. the person getting better at a task

how to control order effects

counter balancing