Engineering Mathematics, Volume II, Second Edition

13

Elements of Statistics and Probability

13.1 Introduction

Statistics is the science of assembling, analysing, characterizing, and interpreting the collection of data (information expressed numerically). The methods used for this purpose are called statistical methods. The general characteristics of data are:

1. Data shows a tendency to concentrate at certain values, usually somewhere in the centre of the distribution. Measures of this tendency are called measures of central tendency or averages.
2. The data varies about a measure of central tendency and the measures of deviation are called measures of variability or dispersion.
3. The data in a frequency distribution may fall into symmetrical or asymmetrical patterns. The measures of the degree of ...