Type of data

• Qualitative data

  Non-numerical data expressed in words

  1. Strength - richness of detail. Much broader in scope than qualitative data. More meaningful, greater external validity.
  2. Limitation - difficult to analyse. Hard to identify patterns and make comparisons. This leads to subjective interpretation and researcher bias.
• Quantitative data

  Numerical data

  1. Strength - easier to analyse. can draw graphs and calculate averages. so comparisons between groups can be made
  2. Limitation - narrower in meaning. expresses less detail than qualitative data. lower external validity may be less like real life.
• Primary data

  First hand data collected for the purpose of the investigation

  1. fits the job. study designed to extract only the data needed. information is directly relevant to research aims
  2. requires time and effort. designing and collating questionnaires takes time and expense.n secondary data can be accessed within minutes.
• Secondary data

  Collected by someone other than the person who is conducting the research

  1. Strength - inexpensive. the desired information may already exist. requires minimal effort making it inexpensive
  2. Limitation - Quality is poor. information may be outdated or incomplete. challenges the validity of any conclusions.
• Meta-analysis

  A type of secondary data that involves combining data from a large number of studies . Calculation of effect size.

  1. Strength - increases validity of conclusions. The eventual sample size is much larger than individual samples. Increases the extent to which generalisations can be made.
  2. Limitation - Publication bias. Researchers may not select all relevant studies, leaving out negative or non significant results.