Validity

• What is validity

  refers to the extent to which a study has tested or measured what it set out to measure/is it true to the aim
• What is internal validity


  refers to how well a study measures what it set out to measure at the start of the research e.g if a personality test accurately measures a participant's personality traits
• How is validity increased


  if there is a lot of control implemented in the procedure. any controls that aren't what the researcher is specifically measuring (extraneous variables) could impact the procedure and results so must be controlled. this allows the researcher to simply measure what they set out in their aim and not allow any other variables to impact upon that e.g how temperature affects mood, don't want any other factors such as weather (extraneous variable) to impact mood
• What leads to high internal validity

  high controls over extraneous variables = high internal validity. if extraneous variables aren't controlled they can confound the results and the validity of the research can be questioned
• What are the 5 type of extraneous variable

  • situational variables
  • individual differences
  • researcher effects
  • demand characteristics
  • social desireability
• Situational variables


  any factors within the environment that can affect participants behaviour/results e.g noise, time of day, crowded/isolated places, temperature etc
• Individual differences


  any differences between participants not accounted for e.g age, gender, mood, background, ethnicity, IQ etc
• Researcher effects

  if the researcher acts differently to different participants/conditions (e.g way instructions are delivered) it can influence different behaviours. they shouldn't give any cues to P's about what is expected of them that could encourage certain behaviours (e.g demand characteristics)
• Demand characteristics


  when the participant figures out the aim so behaves in a way that they think the researcher wants to see. unnatural behaviour. (these aren't order effects)
• Social desirability

  when a participant behaves in a way that makes them seem socially desirable and acceptable but may not be their truthful behaviour
• What is external validity


  refers to the extent to which the findings of a study can be generalised to factors outside of the research.
• External validity example Q


  outline one thing that could effect the generalisability of this study
• What is ecological validity

  refers to whether the task and/or setting reflect real life situations and can therefore be applied/generalised to real life situations. if it does then the study has high ecological validity and therefore mundane realism (EV)
• What is population validity


  refers to whether the sample involved in the study is representative of the wider target population of the study. if a study has low population validity then there will be difficulties in generalising the results to other individuals therefore reducing the usefulness of the study
• Population validity example Q


  who is the target population? Does the sample reflect this?
• What are the two types of external validity/reliability

  ecological validity and population validity
• What are extraneous variables


  factors outside of the research that could change the validity of the study. if not controlled, may become confounding variable
• What are controls


  a way to control confounding variables: to control a variable precisely to remove it as a confounded variable (to remove the factors affecting your research)
• What does generalisable mean 


  are the results valid enough that they can be used to make assumptions about how the target population would behave
• What part of the study is internal validity related to


  the procedure
• What part of the study is ecological validity related to


  the task and setting
• What part of the study is population validity related to


  the sample
• How can the internal, ecological and population validity be improved


  internal = high control over EVs

  ecological = the task and setting need to be natural/realistic

  population = select a sample that reflects the target population
• What is face validity


  refers to the extent to which something looks as if it will measure what it's supposed to measure
• What is construct validity


  the extent to which a test measures all aspects of behaviour in question e.g driving ability - hazard perception, steering, clutch control, speed etc
• What is criterion validity


  refers to the extent to which the scores on one measure are able to predict the outcome on another related measure. it consists of two types of validity: concurrent and predictive
• What is concurrent validity


  refers to the extent to which a test correlates (concurs) well with a measure of the same thing that has been previously validated. to test: compare the results of your new measure with a previously validated measure e.g invention of a new test for language ability 2024 - is this similar to the test on language ability from 2005?
• What is predictive validity


  refers to the extent to which a measure can predict future behaviour or attitude e.g if an IQ test from 5 years ago, predicts/is positively related to GCSE performance it would have criterion validity