In this problem, assume that the distribution of differences is
approximately normal. Note: For degrees of
freedom d.f. not in the
Student's t table, use the
closest d.f. that is smaller.
In some situations, this choice of d.f. may
increase the P-value by a small amount and therefore
produce a slightly more "conservative" answer.
Are America's top chief executive officers (CEOs) really worth all
that money? One way to answer this question is to look at
row B, the annual company percentage increase in
revenue, versus row A, the CEO's annual percentage
salary increase in that same company. Suppose a random sample of
companies yielded the following data:
B: Percent increase
for company
14
16
12
18
6
4
21
37
A: Percent
increase
for CEO
19
26
16
14
-4
19
15
30
Do these data indicate that the population mean percentage
increase in corporate revenue (row B) is different
from the population mean percentage increase in CEO salary? Use a
5% level of significance. Solve the problem using the critical
region method of testing.
(Let d = B ā A. Round
your answers to three decimal places.)
test statistic
=
critical value
= Ā±
In this problem, assume that the distribution of differences is
approximately normal. Note: For degrees of
freedom d.f. not in the
Student's t table, use the
closest d.f. that is smaller.
In some situations, this choice of d.f. may
increase the P-value by a small amount and therefore
produce a slightly more "conservative" answer.
Suppose that at five weather stations on Trail Ridge Road in Rocky
Mountain National Park, the peak wind gusts (in miles per hour) for
January and April are recorded below.
Wilderness District
1
2
3
4
5
January
129
131
126
64
78
April
113
95
106
88
61
Does this information indicate that the peak wind gusts are
higher in January than in April? Use š¼ = 0.01. Solve
the problem using the critical region method of testing.
(Let d = January ā April. Round
your answers to three decimal places.)
test statistic
=
critical value
=