Describe how you understand ANOVA Case Study Example | Topics and Well Written Essays - 250 words

Describe how you understand ANOVA - Case Study Example In order to contain the error and compare all groups simultaneously, the Analysis of Variance or ANOVA may be used. The ANOVA is a statistical method that compares the variance associated with groups of scores and the variance associated with individual differences among scores in order to test the significance of the difference between groups (Guilford, & Fruchter, 1973). According the Bass (2007), the ratio of the variance between groups (which occurs due to differences in the treatments) and the variance within groups (due to individual differences) tells us the extent to which the total variance may be attributed to the treatments or group distinctions. The null hypothesis for the ANOVA is that â€Å"the means for each group are the same at a given level of significance†, while the alternate hypothesis states that â€Å"the means are significantly different from each other†. The alternate hypothesis is true when the variations in the treatment levels are not due to error or individual differences but due to the differences in the treatment levels. This concept is explained very well by Bass (2007). Although it is important that these criteria be met in order for the statistic value to be strong and reliable; a slight deviation from the ideal is acceptable as the ANOVA is quite a robust statistic. The ANOVA statistic is calculated as the F statistic, and is based on the F distribution of scores (Bass, 2007). If the calculated value of the ANOVA is equal to or higher that the F statistic presented at the stated level of significance; then we reject the null hypothesis. On the other hand, if the F value calculated is lower to the tabulated value, we accept the null