methodology Flashcards
what is an independent variable?
the factor that will be changed in an experiment
what is a dependent variable?
the factor that will be measured/observed
what is an extraneous variable?
factors that may impact the experiments results unintentionally
e.g. demand characteristics, situational variables
what are confounding variables?
extraneous variables that vary with the IV so we cannot be sure of the true source of change to the DV
what does it mean to operationalise variables?
clearly describing the IV and the DV in terms of how they will be manipulated and measured
what is a hypothesis?
a formal statement/prediction of what the researcher expects to find. needs to be testable.
what is a directional one-tailed hypothesis?
this predicts the effect of the IV on the DV e.g. ‘adults will recall more words than children’
what is a non-directional two-tailed hypothesis?
this predicts that the IV will effect the DV but does not specify a direction e.g. ‘there will be a difference in the amount of words recalled by children and adults’
what is a null hypothesis?
this predicts there will be no relationship between the two variables - one will not effect the other. Any correlation is due to chance factors
what are the types of participant design?
- independent measures
- repeated measures
- matched pairs
what is an independent measures pt design?
different participants are used in each condition of the experiment/study
what is a strength of independent measures pt design?
PTs are less likely to guess the aim of the study
PTs will not grow fatigued and do worse on later conditions
what is a weakness of independent measures pt design?
more people are needed for the study, time and money consuming
differences between PTs are more likely to effect results
what is a repeated measures participant design?
the same participants are used in each condition
what is a strength of repeated measures pt design?
pt variables are reduced
fewer people need to be recruited
what is a weakness of repeated measures pt design?
practice effect (learn the experiment so do better in later conditions) fatigue effect (tired so do worse later)
what is a matched pairs participant design?
different participants are used in each condition, but they are matched on all important characteristics e.g. age, gender, intelligence
what is a strength of matched pairs pt design?
reduced participant variables, without practice or fatigue
what is a weakness of matched pairs pt design?
very time consuming matching pairs so specifically
what is a sample?
a group of people from the target population to take part in a study
what are the different types of sampling that can be used?
- random
- stratified
- volunteer
- opportunity
what is random sampling?
participants are chosen at random from the population, everyone has equal chance of being selected
strength of random sampling
eliminates sampling bias
weakness of random sampling
difficult - time, effort, money
