Design of Experiments and
Analysis of Variance
Chapter 8
8.2
The treatments are the combinations of levels of each of the two factors.
There are 2
×
5 = 10
treatments.
They are:
(A, 50), (A, 60), (A, 70), (A, 80), (A, 90)
(B, 50), (B, 60), (B, 70), (B, 80), (B, 90)
8.4
a.
College GPA's are measured on college students.
The experimental units are college
students.
b.
Household income is measured on households.
The experimental units are households.
c.
Gasoline mileage is measured on automobiles.
The experimental units are the
automobiles of a particular model.
d.
The experimental units are the sectors on a computer diskette.
e.
The experimental units are the states.
8.6
a.
The response variable is the amount of the purchase.
b.
There is one factor in this problem: type of credit card.
c.
There are 4 treatments, corresponding to the 4 levels of the factor.
The treatments are
VISA, MasterCard, American Express, and Discover.
d.
The experimental units are the credit card holders.
8.8
a.
The response variable in this problem is the consumer’s opinion on the value of the
discount offer.
b.
There are two treatments in this problem:
Within-store price promotion and between-
store price promotion.
c.
The experimental units are the consumers.
8.10
a.
There are 2 factors in the problem:
Type of yeast and Temperature.
Type of yeast
has 2 levels – Brewer’s yeast and baker’s yeast.
Temperature has 4 levels – 45
o
,
48
o
, 51
o
and 54
o
C.
b.
The response variable is the autolysis yield.
c.
There are a total of 2
×
4 = 8 treatments in this experiment.
The treatments are all the
type of yeast-temperature combinations.
d.
This is a designed experiment.
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Chapter 8