Control Of Variables Flashcards
Why do we need to control variables?
Only the IV should affect the DV so any other variables should be removed or well controlled as it could cause the results to be distorted
What is an extraneous variable and what are some examples?
Any variable that may have an effect on the DV (nuisance variables)
Gender, age
What are confounding variables?
Any variable that may affect the DV so we can’t be sure of the true source of the changes to the DV
Vary systematically with the IV
What are demand characteristics?
Any cue from the researcher of the research situation that may be interpreted by the p’s as revealing the aim of the investigation
Could cause the p’s behaviour to change: please u effect/screw you effect (affects validity as behaviour not natural)
What are investigator effects and what are some examples?
Any unwanted influence from the researchers behaviour on the research outcome
Can be unconscious/conscious
- physical characteristics (age, ethnicity, gender)
- unconscious cues (smiling, nodding)
- leading questions
- investigators may be unconsciously biased
What is standardisation?
Using exactly the same formalised procedures and instructions for all p’s in a research study
Give psychology scientific credibility
What is randomisation?
Use of chance to reduce the effects of bias from investigator effects
Can be done for the design of materials or deciding the order of conditions
