Answer Key for Quiz #2
STAT404
October 28, 2012
Problem 1
Notice that the slopes between 1.0 and 1.5 water level are noticeably dierent. You
should be able to plot this by hand given the numbers in our data. The plot with cover
on the x-axis is not as inf
Answer Key to Quiz #3 of STAT404
Problem 1
I = 124 = 235 = 1345
Problem 2
Resolution III. The implication is that the Main eects will be aliased with the 2-factor
interaction eects.
Problem 3
There should be 5 main eects and 10 2-factor interactions. In a
Answer Key for Quiz #1
STAT404
October 16, 2012
Problem 1
Either
Yij = + i + ij ,
i = 1, . . . , 4; j = 1, . . . , 3
(1)
or
Yij = i + ij ,
i = 1, . . . , 4; j = 1, . . . , 3
(2)
is the overall mean eect and i is the eect of treatment i. 11 , 12 , . . . ,
1. Solution
(a) solution
The model for this problem would be
Yijk = + i + j + k +
ijk
i, j, k = 1, 2, 3
where, i = the eect of time at level i
j = the eect of temperature at level j
k = the eect of Acid at level k
and ijk = the random error term.
ijk
iid
Appendix D
Contrast Matrices for 23 and 24
Factorials
Tables D.1 and D.2 give contrast matrices for 23 and 24 experiments, respectively.
They are useful for making a plan showing the runs in a blocked design. For example,
with a 23 design in two blocks an
7-12
7.6. EXERCISES
7.6 A chemistry professor wants to run a 24 experiment in treatment factors A, B,
C, and D. Four laboratory technicians are available, and each has time to make
four of the runs. To reduce the impact of technician-to-technician variabi
1. Solution
In this problem, there are four treatment factors (two-level), four blocks (one block factor with
four levels) and four runs per block.
2. Solution
From table 7.5, the design generators for pseudo factors B1 and B2 are:
B1 = 123;
B2 = 124
3. S