TYPES OF DATA

• Primary data


  Data collected at source e.g. from running an experiment, conducting a questionnaire
• Secondary data


  Data that has not been collected at source, obtained by other researchers
• Meta-analysis


  1. Researcher conducts statistical analysis of quantitative findings from multiple published studies

  2. Combines findings to draw overall conclusion

  3. Results expressed in terms of effect size
• Meta-analysis


  • Bias is reduced as researcher has not personally conducted original research
  • Reliability should be high as large number of studies analysed statistically
• Quantitative data


  Data in the form of numbers
• Qualitative data


  Data in the form of words e.g. thoughts, feelings, attitudes, ideas, beliefs
• Measures of central tendency


  Statistics that describe the central or typical value of a data set
• Mean


  Calculates the average score of a data set
• Mode


  Calculates the most frequently occurring score in a data set
• Median


  Calculates the middle value of a data set
• Measures of dispersion


  Calculate the spread of scores and how much they vary from the mean or median
• Range


  Difference between the lowest and highest scores in a data set
• Standard deviation


  Calculates how a set of scores deviates from the mean