CAS Exam MAS-II Spring 2019, Question 14
Study guide: Exam MAS-II
You are fitting a Linear Mixed Model to determine the effect of different preservatives on the shelf life of apples. You are given the following information:
- Each apple is cut into three pieces and treated with a different preservative.
- The measured between subject variance is 1.43 and the within subject variance is 0.87.
Determine which of the following matrices is the variance-covariance matrix for a randomly selected subject for the Implied Marginal Model.
- A)
\begin{bmatrix} 1.43 & 1.43 & 1.43 \\ 1.43 & 1.43 & 1.43 \\ 1.43 & 1.43 & 1.43 \end{bmatrix} - B)
\begin{bmatrix} 0.87 & 0 & 0 \\ 0 & 0.87 & 0 \\ 0 & 0 & 0.87 \end{bmatrix} - C)
\begin{bmatrix} 2.30 & 1.43 & 1.43 \\ 1.43 & 2.30 & 1.43 \\ 1.43 & 1.43 & 2.30 \end{bmatrix} - D)
\begin{bmatrix} 0.87 & 1.43 & 1.43 \\ 1.43 & 0.87 & 1.43 \\ 1.43 & 1.43 & 0.87 \end{bmatrix} - E)
\begin{bmatrix} 2.30 & 2.30 & 2.30 \\ 2.30 & 2.30 & 2.30 \\ 2.30 & 2.30 & 2.30 \end{bmatrix}
Answer this question and see the worked solution