types of experiments

Cards (22)

  • types of experiments in psychology
    • laboratory
    • field
    • natural
    • quasi
  • laboratory experiments are conducted in highly controlled environments
  • in field experiments the independent variables are manipulated in a natural more every day setting
  • natural experiments are those when the researcher takes advantage of pre existing independent variables
  • quasi experiments have an independent variable based on existing difference between people (age, gender) - noone has changed the variable because it already exists
  • pilot studies are trail versions of proposed studies to test their effectiveness and make improvement
  • pilot studies are helpful to identify potential issues which can then be rectified before commiting to the real study
  • standardisation refers to process which procedures used in research are kept the same
  • demand characteristics are where participants change their natural behaviour because they know they are being watched
  • social desirability bias is a type of bias in participants behaviour which occurs when they note aspects of the study that have to do with particular social norms or expectations, therefore presenting themselves in what they deem to be socially accepted.
  • investigator effects is where a researcher acts in way to support their prediction (can be conscious or unconscious)
  • laboratory experiment strengths
    • high degree of control over environment because it is in a controlled setting - high internal validity
    • replicable - due to high levels of control, the research procedures can be repeated so reliability of results can be checked
  • laboratory experiment limitations
    • lacks ecological validity - findings cannot be generalised to real life settings due to involvement of researcher in manipulating and controlling multiple variables - poor external validity
    • participants are aware of them being studied (demand characteristics)
  • field experiment strengths
    • validity - can have some degree of control alongside being conducted in natural environment - seen as to have reasonable internal and external validity
  • field experiment limitation
    • less control - less control than lab experiment so extraneous variables are more likely to distort findings - internal validity will be lower
  • the aim of a pilot study is to provide necessary info which can help identify potential issues that can later be rectified
  • nominal data cannot be measured such as colours
  • ordinal data is able to be ordered such as numbers
  • strengths for natural experiments
    • has high external validity because it is being studies naturally rather than being manipulated artificially
    • unique insights gained in real life situations which cannot be measured through other experiments
    • investigating naturally occuring IV allows research to be conducted into areas which may have ethical issues if experimented
    • reduced risk of demand characteristics
  • limitations of natural experiments
    • no control over environment and extraneous variables results may be affected
    • these types of experiments occur rarely - limits opportunity to apply results
    • ethical issues e.g consent of individuals to be within the study
  • strengths of quasi experiments
    • experiment allows us to compare different types of people easily - provides an insight into similarities and differences that could not be ethically studied
  • limitations of quasi experiments
    • participants cannot be randomly allocated to remove bias in procedure since IV is naturally occuring difference between each participant - psychologists will be less certain that IV alone will have caused affect as other environmental factors may have played a role