Sampling

• Random Sampling :

  Involves producing a random list of individuals to survey. Those picked could be generated randomly, using a computer and the telephone directory or the electoral register.
• Random Sampling:

  advantages

  • There is no chance of bias being introduced when selecting individuals for the sample.
  • It is simple to draw up a sample.
• Random Sampling:

  disadvantages

  • It may not be focused on any particular market segment.
  • It assumes that all members of the group are the same, which is not always the case.
  • It is an expensive method to administer and run.
• Stratified Random Sampling:

  A sample that is representative of the target market.
• Stratified Random Sampling:

  advantages

  • The sample will represent the target market.
  • No researcher bias as the sample is random.
• Stratified Random Sampling:

  disadvantages

  • Sample could be geographically dispersed, adding to the cost of research.
• Quota Sampling:

  The researcher chooses from a group of people with certain characteristics.
• Quota Sampling:

  advantages

  • It is cheaper to operate than random Sampling as it needs fewer resources.
  • Statistics are available showing the proportions of different groups within the population that are readily available.
• Quota sampling:

  disadvantages

  • Results can be less representative than than using the random sampling method.
  • It is easier to introduce bias which may affect the results.