18.24a
b. b4 = 1505.6; after removing the effect of age, education, and weekly hours of work people who
work for themselves earn on average $1505.60 less than people who work for someone else.
18.25 Let
PARTYID3-1 = 1, if Democrat
=0, if not
t = -4.13, p-value = 0. There is sufficient evidence to infer that Democrats are more likely than
Independents to believe that government should reduce income differences after removing the
effects of age, income, education, and weekly hours.
b. H0:β6 = 0
18.26 Let
POLVIEWS3-1 = 1, if liberal
=0, if not
a. H0:β5 = 0
H1:β5 < 0
t = -6.15, p-value = 0. There is sufficient evidence to infer that liberals are more likely than
b. H0:β6 = 0
H1:β6 > 0
t = 6.17, p-value = 0. There is sufficient evidence to infer that conservatives are more likely than
18.27
. H0:β2 = 0
18.28 Let
POLVIEWS3-1 = 1, if liberal
=0, if not
a. H0:β5 = 0
H1:β5 < 0
t = -5.06, p-value = 0. There is sufficient evidence to infer that liberals are more likely than
moderates to believe that government help poor people after removing the effects of age, income,
education, and weekly hours.
18.29
18.30 Let
RACECAT1 = 1, if White
= 0, if not
Compare whites and others
H0:β2 = 0
H1:β2 ≠ 0
18.31 Let
PARTYID3-1 = 1, if Democrat
=0, if not
a. H0:β5 = 0
H1:β5 < 0
t = -4.17, p-value = 0. There is sufficient evidence to infer that Democrats are more likely than
Independents to believe that government should help poor people after removing the effects of
18.32
t = 2.45, p-value = .0144. There is enough evidence to infer that there are differences in income
between Americans born in the United States and those born elsewhere after removing the effects
of age, education , and weekly hours of work.
18.34
a
:H0
0
54321 =====
:H0
1
2
14
3
4
15
16
17
18
19
20
21
22
A B C D E F
SUMMARY OUTPUT
Regression Statistics
Multiple R 0.9737
Coefficients Standard Error t Stat P-value
Intercept -5916 3141 -1.88 0.0627
Years 1022 48.93 20.88 0.0000
PhD 725.7 961.5 0.75 0.4523
Evaluation 3729 619.8 6.02 0.0000
Articles 439.1 80.7 5.44 0.0000
Gender 1090 632.0 1.72 0.0879