seminare 3

• SEMINAR 3 - QUANTITATIVE RESEARCH METHODS IN PSYCHOLOGY AND COGNITIVE SCIENCES AND STATISTICS II
• What we're gonna discuss

  • Research designs
  • Samples and sampling
  • Sampling methods
  • Internal versus External Validity
• Internal validity


  The DV is the result of the IV manipulation
• External validity


  The relationship between VI and VD is also stable at the level of other groups -> GENERALIZATION
• Quantitative methods


  • Usually answer the question: "How many or how many/much?"
  • Data is usually numeric (working with large data sets)
  • Approach based on testing and measuring
  • Statistical analysis
• Qualitative methods


  • They answer the question: "Why?"
  • Data are observations, words or symbols
  • Observational approach
  • Non-statistical analyses
• Research designs


  • Randomization
  • Random assignment
  • Random selection
• 3 conditions must be met for experimental designs: IV manipulation, Random allocation of participants, Random selection of participants
• Random allocation is different from random selection
• Important symbols to keep in mind

  • Type
  • Sub-design name
  • Symbol
  • Strengths
  • Limitations
• Pre-experimental designs


  • One-shot case study
  • One group pre-test – post-test
  • Static group design
• True experiments


  • Post-Test Only Control Group Design
  • Pre-Test - Post-Test Control Group Design
  • Solomon Four Group Design
• Quasi-experimental Designs


  • Non-Equivalent Control Group Designs
  • Time Series Designs
• Non-experimental designs


  • Cross-sectional (transversal)
  • Longitudinal
  • Repeated measures
  • Cohort studies
• Sample


  The group of people that is selected for study participation
• Sampling


  • The process of selecting a sample
  • Can be probabilistic (random) and non-probabilistic (not random)