Assignment 4
Due 2/19/01

1. For a random model and the data from exercise 5.12, estimate the variance components using Type I and Type III SS's with Proc GLM.

   You can use the random statement to obtain the expected mean squares and the /E1 or /E3 option in the model statement to get the Type I or Type III expected mean squares.

2. Obtain approximate standard errors for the estimated variance components.
3. Create a module that given the vectors y, a, and b will return estimates of the variance components and standard errors for a random 2-way crossed classification:
   1. using Type I SS's.
   2. using Type III SS's