In most statistical applications a random sample is taken from the population under investigation, a statistic is computed from the sample data, and conclusions are drawn about the population on the basis of this sample. A sampling distribution is the distribution of all possible values of the sample statistic that can be obtained from the population for a given sample size. For instance, a random sample of 100 persons might be taken from a population and weighed and then their mean weight computed. This sample mean (X) can be thought of as having been drawn from the distribution of all possible sample means of sample size 100 that could be taken from the population. Similarly, each sample statistic that can be computed from sample data can be considered as having been drawn from a sampling distribution.