This test examines the equality of variances for multiple waves.

To execute Bartlett's version of the test, use the following command:

The results are displayed in the Variances Test table:

Bartlett's statistic is smaller than the critical value and so we can't reject the equality of the variances of the waves. To execute Levene's test using the means of the waves select the blue line below and type Ctrl-Enter:

The results are displayed in the Variances Test table:

Levene's test statistic is also smaller than the critical value and so H₀ can't be rejected. To execute Levene's test using the medians of the waves select the blue line below and type Ctrl-Enter:

The results are displayed in the Variances Test table:

To execute Levene's test using 10% trimmed means of the waves select the blue line below and type Ctrl-Enter:

The results are displayed in the Variances Test table:

Both modified Levene's tests agree with the original and with Bartlett's test -- H₀ can't be rejected. If we replace the wave data4 with data5:

Perform Bartlett's test:

In this case the Bartlett's test statistic is larger than the critical value and H₀ is rejected. You will get similar results if you execute any of the modified tests as shown below:

Levene's Test

Modified Levene's test using the median

Modified Levene's test using 10% trimmed mean