Pilot studies

• A small scale investigation that takes Place before th real investigation is conducted.

  • a trial run
• Aim of a pilot study

  • to ensure the materials and procedures run smoothly
  • allows the research design to be amended
  • researcher can identify issues that can be rectified before committing to the full length / expense of the real investigation.
• Floor effect

  • pilot study can be useful to identify a ‘floor effect’
  • sometimes the task is too hard bc none of the pp’s (or a large proportion of pp’s) can’t score at all.
  • so performance is largely low - meaning it’s difficult to differentiate among the many individuals at that low level
  • this skews the distribution of scores
• Ceiling effect

  • sometimes the task is too easy so many of the pp’s perform highly
  • this means it’s difficult to differentiate among the many pp’s scoring at that high level
  • this skews the distribution of scores
• To avoid bias, pilot studies are usually carried out on individuals who are similar to the target population - but not those who will be part of the final sample.