Types of data

• Quantitative data

  • Expressed numerically
  • Easy to analyse
  • Less detail
  • Less open to bias
• Qualitative data

  • Expressed in words
  • Written description
  • Collected through experiments and questionnaires
  • Rich in detail
  • Greater external validity
  • More difficult to analyse
  • Subject to bias
• Primary data

  • Original
  • Collected by researcher specifically for the purpose of the investigation
  • First-hand from the participants themselves
  • Experiments, questionnaires, interviews and observations
• Secondary data

  • Collected by someone other than the researcher who is conducting the research
  • Data that already exists before the psychologist begins their research
  • ’Desk research’
  • Already been subject to statistical analysis
  • Inexpensive and minimal effort
  • May be outdated or incomplete, challenging validity
• Primary data

  • Original
  • Collected by researcher specifically for the purpose of the investigation
  • First-hand from the participants themselves
  • Experiments, questionnaires, interviews and observations
  • Authentic
  • Time and effort. Considerable planning, preparation and resources