1. How good/useful is the data provided

1. How good/useful is the data provided

1. Types of data

   • Nominal data
     • Qualitiative
     • No ranking
   • Types of data
     • Ordinal Data
       • Quantitative & Qualitative
       • Ranking
     • Cardinal Data
       • Numbers
       • Ranking
       • Measurable comparison
     • Discrete data
       • measured of precision
       • labelled data
     • Continuous data
       • Quanititve
       • Measured only

2. Types of sampling

   • non-random
   • random
   • stratified
   • cluster

3. Collecting data

   • Observations
   • Experiments
   • Surveys: interviews / Questionaires