qA statistic is
calculated from a batch of data.
qThe value of the
statistic varies from batch to batch.
qA sampling
distribution for a statistic is the probability distribution describing batch-to-batch variations of that statistic.
qThe random variations
of sample statistics can be described using
probability distributions just as the random variations of the underlying data can be described using probability distributions.
qSample statistics can
be viewed as having been drawn from probability
distributions.