Introduction

Abstract

Statistics is the science of data. The term statistics is derived from the New Latin statisticum collegium (“council of state”) and the Italian word statista (“statesman”). In a statistical investigation, it is known that for reasons of time or cost, one may not be able to study each individual element (of population). Consider a manufacturing unit that receives raw material from the vendors. It is then necessary to inspect the raw materials before accepting it. It is practically impossible to check each and every item of raw material. Thus, a few items (sample) are randomly selected from the lot or batch and inspected individually before taking a decision to reject or accept the lot. Consider another situation where one wants to find the retail book value (dependent variable) of a used automobile using the age of the automobile (independent variable).