3.3.2 Analysis of Variance
Analysis of variance (ANOVA) is a technique that use test-based variance ratios to determine whether or not significant differences exist among means of several groups of observations, where each group follows a normal distribution. ANOVA also extends to t-tests used to determine whether or not two means differ in the case where there are three or more means.
The analysis of variance for response surface quadratic model for response 4 (total tocopherol content; as vitamin E) was computed as shown in Table 3.5, as it illustrates partial sum of squares of the third type. Results were analysed and compared to know which factor or factors are significant model terms.
Table 3.5 Analysis of Variance (ANOVA) for Response Surface Quadratic model