Analysis of Variance (ANOVA) is used to test differences between two or more group means. . It is used when the factor variable has more than one group.ANOVA test is the different sources of variation in a typical variable. A primarily ANOVA test gives the evidence of the mean equality between the group. This statistical method is an extension of the t-test.
The one-way analysis of variance (ANOVA) is also known as one-factorANOVA. It is an extension of independent two-samples t-test for comparing means when there are more than two groups. The data is organized into various groups based on single variable called factor variable.
ANOVA test hypotheses:
• Null hypothesis: Same means of different groups.
• Alternative hypothesis: At least one sample mean is not equal to the others.
Working of one-way ANOVA
Suppose we have 3 groups (A, B, and C) to compare:
1. Compute the common variance, which is called variance within samples.
2. Compute the mean of each group.
3. Compute the variance between sample means.