research methods year 1

• what are independent variables?

  an aspect of the experimental situation that is manipulated by the experimenter
• what are dependent variables?

  the variable that is measured the investigator
• what is a hypothesis?

  a clear, precise, testable statement that states the relationship between the variables to be tested
• what does operationalisation mean?

  clearly defining variables in terms of how they can be measured
• what is a directional-hypothesis?

  suggests a specific outcome, used when theory or previous research suggest an outcome
• which is a non-directional hypothesis?

  doesn't suggest a specific outcome, used when there's no theory or previous research is contradictory
• what are extraneous variables?

  any variable other then the IV that may affect the DV if it's not controlled e.g. the lighting in a lab
• what are confounding variables?

  a kind of EV that varies systematically with the IV, so we can't tell whether any change in the DV is due to the IV or CV
• what is investigator effect?

  any effect of the investigator's behaviour on the research outcome e,g, interaction with ps
• what are demand characteristics?

  any cue from the investigator or from the research process that may be interpreted by the ps as revealing the purpose of the investigation. May be lead to ps changing their behaviour within the research situation
• what is randomisation?

  the use of chance methods to control for the effects of bias
• what is standardisation?

  using exactly the same formalised procedures and instructions for all ps in a research study
• what is the experimental method?

  aim, hypothesis, variables
• what are experimental designs?

  the way in which ps are used in an experiment
• what are independent groups?

  ps are allocated to different groups where each group represents one experimental condition
• what are repeated measures?

  all participants take part in all conditions of the experiment
• what are matched pairs?

  pairs of ps are first matched on some variables that may affect the DV. One member of the pair is then assigned condition A, and the other condition B
• what are lab experiments?

  an experiment that takes place in a controlled enviroment within which the researcher manipulates the IV and records the effect on the DV, whilst controlling Ev
• what is a strength of lab experiments?

  high control over CV and EV (high internal validity), replication is easier due to high levels of control
• what is a limitation of lab experiments?

  lack ecological validity as it's an artificial environment, more likely to see demand characteristics
• what are field experiments?

  takes place in a natural environment within which the researcher manipulates the IV and records the effect on the DV
• what is a strength of field experiments?

  high external validity, produce more valid and accurate behaviour,
• what is a limitation of field experiments?

  loss of control extraneous variables and control variables, ethical issues as ps may not know they are being studied
• what is a Quasi experiment?

  a study where the IV hasn't been determined by anyone, the variables simply already exist
• what is a strength of quasi experiments?

  controlled conditions, replicable
• what is a limitation of quasi experiments?

  can't allocate ps to conditions so may be CV, IV isn't deliberately changed so we cant claim the IV has caused any observed change
• what is a natural experiment?

  the change in IV isn't brought around by the researcher, but would've happened even if the researcher wasn't there
• what is a strength for natural experiments?

  can provide opportunities for research that may not otherwise be undertaken for practical or ethical reasons e.g. Romanian orphanages
• what is a limitation of natural experiments?

  can't really be generalised as there are usually a lack of similar situations, ps may not be randomly allocated to experimental conditions meaning the researcher is less sure whether it was the IV that affected the DV
• what is a random sample?

  all members of target population have equal opportunity of being selected e.g. random number generator
• what is an evaluation of random sampling?

  unbiased increasing internal validity, difficult and time consuming, may be unrepresentative
• what is stratified sampling?

  sample reflects the proportions of people in certain sub-groups within the population
• how is stratified sampling carried out?

  researcher identifies different strata (subgroups) in a population, then the proportions needed for the sample to be representative. PS are then selected using random sampling
• what is an evaluation of stratified sampling?

  easy to generalise as it's representative, identified strata can't reflect all the ways people are different so complete representation is impossible
• what is opportunity sampling?

  investigator selects anyone who is willing and available to take part e.g. asking in the street
• what is an evaluation of opportunity sampling?

  convenient, cheaper, and less time consuming, can be unrepresentative, investigator bias, demand characteristics
• what is volunteer sampling?

  ps select themselves to be part of the sample e.g. through an advert
• what is an evaluation of volunteer sampling?

  less time consuming, ps are more engaged, volunteer bias makes it difficult to generalise
• what is systematic sampling?

  when every nth member of the target population is selected
• what is an evaluation of systematic sampling?

  sampling method is objective, once the system for selection has been established the researcher has no influence over who's selected, time consuming, ps may refuse to take part