experiments

how can order effects be prevented

counterbalancing

what are the two types of hypothesis

research/alternative or experimental hypothesis and null hypothesis

what does operationalising the variable mean

making it measurable

what is a confounding variable

a variable that does affect the results and distort the findings

what is matched pair design

participants are matched in pairs on a variable that needs to be controlled (such as skill level at video games), one from each pair goes in each group

what is a null hypothesis

when no change is predicted

what is an experiment

the manipulation of an IV to see the effects on the DV while attempting to control all extraneous variables

what is an extraneous variable

a variable not under the control of the experiment but could influence the results

what is an independent measures design

each participant only participates in one condition of the study. the two groups are made up of different people

what is counterbalancing

a technique used to deal with order effects when using repeated measures design. the participants sample is split in half and both do each conditons in different orders

what is repeated measures design

each participant takes part in both conditions. the two group are identical

what is an oppotunity sample

pps that are available at the time

what is volunteer sampling

pps select themselves to take part

what is systematic sampling

every nth person is chosen

what is a stratified sample

the proportions in the target population match that in the pps group

what is random sampling

all members of a target population have the same change of being chosen. could pull names out a hat