CONTROL

• Controls


  Experimental controls are used in scientific experiments to prevent factors other than those being studied from affecting the outcome
• Controls are needed to eliminate alternate explanations of experimental results
• Ways to control experiments

  • Randomisation
  • Counterbalancing
  • Standardisation
• Randomisation


  The deliberate avoidance of bias on the part of the researcher in order to keep the research as objective as possible
• Randomisation


  1. Participants are randomly assigned to one condition of the IV

  2. Random allocation to condition ensures that no bias has intruded over which participants take part in which condition

  3. If the procedure involves a list, the list must be decided randomly to avoid researcher bias
• Counterbalancing


  Relevant to repeated measures designs, implemented by splitting participants in half and having one group complete the conditions in one order and the other group complete them in the reverse order
• Counterbalancing


  • Used to control for order effects (practice, fatigue, boredom)
• Standardisation


  The identical procedure set up in an experiment (or the questions used in self-report measures) across all conditions/participants
• Standardisation


  1. Instructions given to participants

  2. Briefing prior to and debriefing after the procedure

  3. Number of participants per condition

  4. Timings for each condition

  5. Identical materials used
• Implementing standardisation allows the research to be replicated and reliable