Analysis of Variance

It is defined as a technique whereby the total variation present in a set of data is partioned into two or more components. Associated with each of these components is a  specific source of variation, so that in the analysis it is possible to ascertain the magnitude of the contributions of each of these sources to the total variation.

Applications of analysis of variance

 Analysis of variance finds its wide application in the analysis of data derived from experiments. the principles of the design of experiments are well covered in several books, including those of Cochran and Cox, Cox, Davies ,Federer, Finney, Fisher, John, Kempthorne, Li and Mendenhall.

Analysis of variance is used for two different purposes, 1- to estimate and test hypothesis about population variances and 2- to estimate and test hypothesis about population means. 

The following given example illustrates the basic ideas involved in the application of analysis of variance. 

Example:-