CHAPTER 1 - Introduction, Scope and Purpose of Applied Statistics

Abstract

This chapter presents the scope and purpose of applied statistics. Applied statistics are concerned mainly with describing and analyzing the variability of various data gathered from a larger collection termed a universe or population. Invariably, every statistical investigation commences with the collection of raw data and its representation in a clearly arranged mode. The raw data may have been obtained by collecting observations or measurements; they may refer to non-numerical qualities, such as the colors and morphological properties of a mineral, or they may comprise numerical quantities, such as lengths and weights. All data must be stored in a databank or cataloged as a list. This inventory is a document representing a basic set of data from which different types of inferences may be derived by analysts. Many empirical frequency distributions can be described more or less accurately by functions with well-known mathematical properties. Typical examples are the normal distribution that seems to be the most usual mathematical distribution function, the binomial distribution that describes the expected frequencies of the occurrence of two alternative states, and the distribution of Poisson that can be shown to describe quantitatively the occurrence of rare events.