Analysis of the Variances for a Monofactor Process

The analysis of the variances of a monofactor process can be used for the indirect testing of both mean values obtained when the process factors take m discrete values. Table 5.38 introduces the preparation of the data for the analysis of the variances of a monofactor process. We can note that each value of the factor must produce m measurements of the process response. 

The data arrangement shown in Table 5.38 can hint that the observable differences from one value to the other, from one column to the other are caused by the factor changes and by the problems of reproducibility. 

In the table, the differences between the columns result from the change in the values of the factors and the differences between the lines give the reproducibility problems of the experiments. The total variance (s ) associated to the table data, here given by relation (5.151), must be divided according to its components the variances of inter-lines (or reproducibility variances) and variances of inter-columns (or variances caused by the factor). 

The result of this division is given in Table 5.39 where the starting data to complete the table have been obtained using the sums Sj, S2 and S3  

Variance origin Sumsofthe Degrees Variances Computed value Theoretical differences of freedom of the Fischer value of the 

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