Mean Square Error Degrees of Freedom Use this option to specify the number of degrees of freedom for the mean square error from the combined ANOVA of the original data with replicates. This information is needed when testing the significance level of each IPCA from the linear-bilinear model. To Specify the Mean Square Error Degrees of Freedom: Check the Input data contains means of genotypes on each environment check box. Enter the desired value in the text box. Acceptable values range from 0 to 10,000.