Variables

• Co-variables look for association or a relationship between the two variables
• Independent variables- researcher manipulates
• Dependant variable- researcher measures
• Pilot studies are conducted as a smaller study of the population in order to standardise instructions and spot extraneous variables
• Extraneous variables- any variable that can influence the measurement of the dependant variable

  (e.g. participant variable, order effect, situational variables and demand characteristics)
• Confounding variables- changes systematically between levels of independent variables
• Peer review- researchers show other experts in their field their research in order to find unaccounted variables or find that it may lack internal validity
• Controlling participant variables- random allocation and matched pairs
• Controlling order effect- counterbalancing
• controlling situational variables- standardisation
• controlling demand characteristics- single/double blind trials
• participant variables- characteristics of the participants that may influence the results of the study
• order effect- when a participant had taken part in one condition they may alter their behaviour for the second condition (fatigue or improvement in the test)
• situational variables- environmental factors
• demand characteristics- altering behaviour as a result of participant trying to help or hinder the study as a result of what they think the aim is