Answers to Selected Exercises
ANS-13
4. Is the sample large enough? Possibly, depending on the size of the faculty. Is the sample representa-
tive? No, they are all from one department. Other departments may tenure far fewer applicants for
tenure.
E
X E R C I S E
11.4
I. 1. c Strong and reliable.
4. c Strong and reliable. 7. c Strong and reliable.
10. c Strong and reliable.
E
X E R C I S E
11.6
1. 2: The skills involved are very different. 4. 5: There are big differences between a small family
budget and a large city budget. 7. 7: The argument does not claim very much, and
considering Jordan’s athletic ability, love for the game, and practice, it isn’t unreasonable to claim
he could learn to play tennis fairly well. 10. 3: The conclusion is too strong in claiming he must
be “ just like” the character. There are a couple of important similarities but not enough to fully sup-
port the conclusion.
E
X E R C I S E
11.8
I. 1. Strong.
4. Weak.
II. 1. a. Strengthen.
b. Strengthen. c. Weaken.
d. Strengthen. 4. a. Strengthen.
b. Weaken. c. Weaken.
d. Strengthen.
E
X E R C I S E
11.10
I. 1. Bad evidence.
4. Good evidence. 7. Good evidence.
10. Good evidence.
II. 1. What else did he eat? Did anyone else become sick
from eating it? 4. The percentage of women with breast implants who
have connective tissue disease; the percentage of 4.
p q
r ˜p
˜q p → q
˜q v r ˜p r C
1. T
T T
F F
T T
F 2.
T T
F F
F T
F F
3. T
F T
F T
F T
F 4.
T F
F F
T F
T F
5. F
T T
T F
T T
T 6.
F T
F T
F T
F F
7. F
F T
T T
T T
T 8.
F F
F T
T T
T F
Invalid.
V. 1.
b
→
e ˜ e
... ˜ b
b e
b → e ˜e
˜ b C 1.
T T
T F
F 2.
T F
F T
F 3.
F T
T F
T 4.
F F
T T
T
Valid. 4.
g
→
s ... ˜ g
→
˜ s
g s
˜g ˜s
g → s ˜g → ˜s C
1. T
T F
F T
T 2.
T F
F T
F T
3. F
T T
F T
F 4.
F F
T T
T T
Invalid.
C
H APT ER
11
E
X E R C I S E
11.1
1. Strong. 4. Strong.
7. Strong. 10. Weak.
E
X E R C I S E
11.2
I. 1. Strong. Is the sample large enough? Yes. Is the
sample representative? Yes 4. Weak. Is the sample large enough? Yes. Is the sam-
ple representative? No.
II. 1. Is the sample large enough? No, there are just three
cities. Is the sample representative? No, not neces- sarily; for example, at least two of the cities have
problems with illegal immigration that may add to the crime problem.
