experimental methods

• what is a pilot study?

  checks to see if there are any problems with methodology

  small scale trial run of experiment
• features of lab experiment?

  tightly controlled artificial environment

  iv deliberately manipulated

  dv is measured

  instructions & procedure are standardised

  evs are highly controlled
• features of quasi experiment?

  tightly controlled artificial environment

  pre-existing iv (not changed) e.g age/gender

  dv is measured

  evs are controlled

  instructions & procedure are standardised
• features of field experiment?

  a more natural environement

  iv deliberately manipulated

  dv is measured

  some evs are controlled

  no standardised procedures
• feautures of natural experiment?

  natural environment

  no control of iv -naturally occuring

  dv is measured

  no control of evs

  no standardised procedures
• high internal validity * for lab?

  • conducted in artificial controlled setting with manipulation of iv & control over evs
  • can trust conclusions as we can be more certain that the only thing affecting dv is iv
• high reliability * for lab?

  • uses standardised procedures
  • means everyone can be given exact same experience
  • easier to replicate in saame way & get same results
• low ecological validity X for lab?

  • conducted in artificial environment so may behaviour is less likely to be realistic as its very different from real life situations
  • this affects the extent to which we can generalise the findings to real world
• high reliability * for quasi?

  • uses standardised procedures it means everyone can be given same experience
  • means its easier to repeat study in same way to see if we get same results
• low control of confounding variables X for quasi?

  • does not randomly allocate participants to conditions so there may be confounding variables
  • ? internal valid - these variables can affect the dv so cause & effect relationship cannot be established
• high ecological validity * for field?

  • accurately represents real world as its conducted in natural settings so behaviour more likely to be realistic
  • results can be generalised to real world
• low risk of demand characteristics * for field?

  • participants are more likely to behave naturally as they are less likely to know they are taking part in a study
  • this means its more difficult for them to guess aim & change behaviour accordingly
• low internal validity X for field?

  • evs cannot be controlled as it takes place in more natural setting
  • makes it difficult to guarantee that iv is only thing affecting dv as evs could have played role
• high ecologial validity * for natural?

  • study takes place in the real world so results are going to be more generalisable
  • results are generalisable to real world so may be able to develop practical applications or explain real world behaviour
• low risk of demand characteristics * for natural?

  • participants are less likely to be aware they are taking part in a study so are less likely to guess aim
  • behaviour is more natural & realistic so results are an accurate reflection of how participants would act in real world
• low internal validity X for natural?

  • as its conducted in completely natural environment means no control over evs
  • difficult to guarantee that iv is only thing affecting dv as evs could have played role
• low ecological validity for quasi?

  • conducted in artificial controlled environment
  • behaviour is less likely to be different from real life situations
  • mkaes it difficult to generalise findings to real life behaviours
• high internal validity for quasi?

  • conducted in artificial controlled environment so controls evs
  • means were better able to establish cause & effect between iv & dv
• low reliabilty for field?

  • does not use standardised procedures so its difficult to repeat under exact same settings
  • makes it difficult to check for consistency
• low reliability for natural?

  • its completely naturally occuring event
  • makes it difficult to repeat study in exact same way
  • would have to rely on same naturally occuring event in same way which is unlikely