Statistics: Statistics is usually not studied for its own sake; rather it is widely employed as a highly valuable tool in analysis of problem in nature, physical and social sciences. The word statistics convey a variety of meaning to people, when it is used in different context. Horace Secrist defines statistics as “aggregates of facts, affected to a mankind extent by multiplicity of causes, numerically expressed, enumerated or estimated according to reasonable standards of accuracy, collected in a systematic manner for a predetermined purpose and placed in relation to each other”.

According to Freund and William as mentioned in “Modern Business Statistics”, “Statistics in general are nothing but a refinement of everyday thinking. They are especially appropriate for handling data which are subject to variation that cannot be fully controlled by experimental method and for which we can have only a fraction of the totality of observation which may exist”.

The definition of the term statistics includes the following, and in its absence of these characteristic any numerical data cannot be called statistics.

i) Statistics are aggregate of facts;

ii) Statistics are affected to a marked extent by multiplicity of causes.

iii) Statistics are numerically expressed.

iv) Statistics are enumerated or estimated according to reasonable standards of accuracy.

v) Statistics are collected in a systematic manner.

vi) Statistics are collected for a predetermined purpose.

vii) Statistics should be placed in relation to each other.