Sampling is a type of scientific surveying which can save time and money and give information on the population of animals and plants. There are many different types of sampling; the most useful type ...

The method of simple random sampling (METHOD=SRS) selects units with equal probability and without replacement. Each possible sample of n different units out of N has the same probability of being ...

Systematic sampling means testing a hypothesis by taking several equally spaced items from a larger list, eg selecting the tenth, 20th and 30th visitor to a theme park. This can be particularly useful ...