Extraneous and Confounding Variables Flashcards
What is an extraneous variable?
any variable other than the IV that can cause a change to the DV and affect the results in an unwanted way
What are some examples of extraneous variables?
age
gender
prior knowledge
experimenter effect
What is a confounding variable?
any variable other than the IV that has had an unwanted effect of the DV
= produces measurable change on the DV
What are some extraneous and possible confounding variables?
experimenter effect order effects use of non standardized instructions or procedures individual participant differences placebo effect
What is one way to reduce bias in sampling?
random sampling and stratified sampling
What is the procedure used to ensure the participants do not know what group they are in?
single blind procedure
What is the procedure used when neither the experimenter nor the participants know what group they are in?
double blind procedure
What is used to reduce order effects?
counterbalancing
Procedures and instructions should be what for all participants?
same or identical
What is used to reduce individual participant differences?
repeated measures design