Chpt 1

• Census: a survey accounting for the whole population

  • ADV: results should be accurate
  • DISADV: time consuming + expensive, hard to consumer large quantities of data
• Sampling:

  ADV: less time consuming, easier to consume small data

  DISADV: may not be accurate enough, sample size may not be large enough
• Random sampling:

  • Random number generator
  • Hat draw
  • Divide quantity required by population then sample for every nth person
• Random sampling:

  • ADV: simple and quick, suitable for large samples
  • DISADV: sampling frame required, can be biased
• Stratified sampling: Splitting population into small sub sections then dividing each section by total population then multiplying by required quantity
• Stratified sampling:

  ADV: Sample accurately reflects sample structure, proportional representation

  DISADV: population must be clearly labelled, biased
• Opportunity sampling: sampling people most convenient

  • ADV: easy and inexpensive
  • DISADV: unlikely to represent whole population, biased
• Quota sampling - choosing a group who's characteristics represent the whole population

  • ADV: quick and easy, no sampling frame required
  • DISADV: bias, population has to be divided into a group which takes time