Research issues

• Extraneous variables


  Any variable other than the IV that may affect the DV if it is not controlled, DOES NOT change systematically with the IV.
• Confounding variable


  Type of EV, that varies systematically with the IV. Therefore we cannot tell if any change in the DV is due to the IV or confounding variables.

  E.g In an experiment you are measuring levels of chattiness after drinking an energy drink. If participants come to the experiment in a happy mood they are more likely to be chatty anyway.
• Demand characteristics


  Any cue from the researcher or research method that may be interpretative by participants as revealing the purpose of the investigation. This may lead to a participant changing their behaviour in a research situation.
• Please-u effect


  Participants may act in a way that they think is expected or over-perform to please the experimenter.
• Screw-u effect


  Participants may deliberately under perform to sabotage the results of the investigation.
• Investigator effects


  Any effect of the investigators behaviour (conscious or unconscious) on the research outcome. May include design of the study, selection and interaction of participants during research.

  E.g Leading questions
• Randomisation


  The use of chance methods to control for the effects of bias when designing materials and deciding the order of experimental conditions.
• Standardisation


  Using the same formalised procedures and instructions for all participants in a research study.

  E.g standardised instructions which are read to all participants.