sampling

Cards (12)

  • random sampling
    Every member of the target population has an equal chance of becoming a participant. All people's names in the target population are collected then a certain amount of participants are randomly picked (like names out a hat).
  • evaluations - random sampling
    strength(s):
    -there is no bias involved.
    -can take little time to do.
    -it is easier than stratified sampling.

    Weakness(es):
    -does not represent the target population.
    -could be time consuming if the target population is large.
  • opportunity sampling
    People who you just happen to get hold of become participants. This could be done by going up to people on the street and asking if they want to participate.
  • volunteer sampling
    People volunteer to be in the research - they put themselves forward for it.
  • evaluations - opportunity sampling
    strength(s):
    -it is easy to do.
    -it takes little time.

    weakness(es):
    -investigator bias.
  • systematic sampling
    Every nth person is chosen to take part. People are listed and then every (for example) tenth person is chosen.
  • stratified sampling
    The target population is divided into different strata. The amount of people in each strata is counted then participants are chosen to be in the sample in a way that represents how their strata appears in the target population.
  • evaluations - volunteer sampling
    strength(s):
    -it is the easiest type of sampling to do.

    weakness(es):
    -volunteer bias.
    -not representative of target population.
  • evaluations - stratified sampling
    strength(s):
    -the most representative type of sampling.

    weakness(es):
    -takes a lot of time to get the sample.
    -a full representation of the target population is not possible.
  • evaluations - systematic sampling
    strength(s):
    -objective.
    -easier to do than random sampling.

    weakness(es):
    -might not represent target population.
    -can be time consuming.
  • target population
    The people who researchers want to generalise their finding to.
  • sample
    A smaller group of the target population who take part in the research.