research methods

• hypothesis;

  • directional: states the direction of the relationship or different between the two variables (IV and DV) - used when findings of a previous study suggest certain outcomes
  • non-directional: doesn't state the direction or difference between variables

  IV: manipulated by the the researcher to see the effect on the DV

  DV: the thing you are measuring during an experiment

  operationalisation: researcher clearly defines the variables in terms of how they can be measured
• research issues:

  • extraneous variables: any variable other than IV that may affect the DV - experiment taking place in chilly room
  • confounding variable: becomes difficult to tell if any changes to DV is because of the IV - coffee drinkers may smoke more than non-coffee drinkers
  • standardisation: researcher uses the exact same procedure for all participants
• experimental designs: ways in which participants are used in experiments

  • independent group: two seperate groups experience two different conditions, experiencing only one level of the IV - be compared

  strengths:

  • no order effects, memory test in both conditions may lead to better performance in the second condition

  weakness:

  • differences between the experiments may be down to participants variables as opposed to the IV - one group may have a better memory than the other
• repeated measures design: where all participants take part in all conditions of the experiment

  strength:

  • less participants are needed, less time spent recruiting individuals
  • participant variables are controlled, higher validity

  weakness:

  • demand characteristics, more likely to occur as they are participating in both designs and can guess the aim
• matched pairs: participants are paired together based on matched variables that may affect their DV - seperated in two conditions to avoid confounding variables

  
  

  strength:

  • participants only take part in single condition, meaning that demand characteristics are less likely to affect the outcome of the experiment

  weakness:

  • participants cannot be matched exactly, even when identical twins are used, still different between them that may affect the DV
  • matching them may be time-consuming and expensive, less economical than other designs