Sampling theory is the field of statistics that is involved. with the collection, analysis and interpretation of data gathered. from random samples of a population under study. The application. of sampling theory is concerned not only with the proper.

Descriptive statistics are used to describe or summarize data in ways that are meaningful and useful. For example, it would not be useful to know that all of the participants in our example wore blue shoes. … Central tendency describes the central point in a data set. Variability describes the spread of the data.