Managament accounting

Systematic sampling is a sampling method which works by selecting every nth item after a random start.

Advantages: 1) It is easy to use. 2) It is cheap.

Disadvantages: 1) It is possible that a biased sample might be chosen if there is a regular pattern to the population which coincides with the sampling method. 2) It is not completely random since some items have a zero chance of being selected.

Multistage sampling is a probability sampling method which involves dividing the population into a number of sub-populations and then selecting a small sample of these sub-populations at random. Each sub-population is then divided further, and then a small sample is again selected at random. This process is repeated as many times as is necessary

Advantages: 1) Fewer investigators are needed. 2) It is not so costly to obtain a sample.

Disadvantages:1) There is the possibility of bias if, for example, only a small number of regions are selected. 2) The method is not truly random, as once the final sampling areas have been selected the rest of the population cannot be in the sample. If the population is heterogeneous, the areas chosen should reflect the full range of the diversity. Otherwise, choosing some areas and excluding others (even if it is done randomly) will result in a biased sample.