Null and alternative hypothesis in order to apply Levene’s test:
Levene’s test is used to test the homogeneity of variances of different populations.
Denote the variance of population-1 as
The test hypotheses are given below:
That is, the variances of both the populations are equal.
Levene’s test will be applied by assuming the populations being compared are normal.
When Levene's Test, this would mean that the variance was different for different groups.
Therefore, The means will be equal and the variances will be different.
Levene’s test will be failed when the null hypothesis is rejected.
The null hypothesis will be rejected when the P-value is small.
The P-value will be small when the degrees of freedom is small.
Thus, the df value will be decreases if we fail the Levene’s test.