13.173 H0: (p1-p2) = 0
H1: (p1-p2) > 0
13.174 H0: (p1-p2) = 0
H1: (p1-p2) > 0
13.175 H0: (p1-p2) = 0
H1: (p1-p2) < 0
13.176 H0: (p1-p2) = 0
H1: (p1-p2) < 0
13.177 H0: (p1-p2) = 0
H1: (p1-p2) ≠ 0
13.178 H0: (p1-p2) = 0
H1: (p1-p2) ≠ 0
13.179 H0: (p1-p2) = 0
H1: (p1-p2) ≠ 0
13.180 H0: (p1-p2) = 0
H1: (p1-p2) ≠ 0
13.181
)pp(:H 210 −
= 0
− )pp(:H 211
0
13.182
)pp(:H 210 −
= 0
− )pp(:H 211
0
13.183
)pp(:H 210 −
= 0
− )pp(:H 211
0
13.184a.
)pp(:H 210 −
= 0
− )pp(:H 211
0
b.
)pp(:H 210 −
= 0
− )pp(:H 211
0
c.
)pp(:H 210 −
= 0
− )pp(:H 211
0
13.185
)(:H 210 −
= 0
)(:H 211 −
13.186
)(:H 210 −
= 0
)(:H 211 −
> 0
Two-tail F test: F = 2.57, p-value = 0; use unequal-variances t-test
t = 15.82, p-value = 0. There is sufficient evidence to infer that government employees work less than private-sector
workers.
13.187
)(:H 210 −
= 0
13.188
D0 :H
= 0
D1 :H
0
13.189
)(:H 210 −
= 0
− )(:H 211
0
Two-tail F test: F = .958, p-value = .7726; use equal-variances t-test
13.190
)pp(:H 210 −
= 0
− )pp(:H 211
0
13.191a
)(:H 210 −
= 0
)(:H 211 −
< 0
t = –2.02, p-value = .0218. There is enough evidence to infer that housing cost a percentage of total income has
increased.
13.192a.
)(:H 210 −
= 0
− )(:H 211
0
Two-tail F test: F = 1.10, p-value = .8430; use equal-variances t-test
t = –1.06, p-value = .2980. There is not enough evidence to conclude that men and women differ in the amount of
time spent reading magazines.
)(:H 210 −
Two-tail F test: F = .266, p-value = .0053; use unequal-variances t-test
1
2
3
4
5
6
A B C
t-Test: Two-Sample Assuming Equal Variances
Male Female
Mean 39.75 49.00
Variance 803.88 733.16
Observations 20 20
13.193a
D0 :H
= 0
D1 :H
0
13.194
)pp(:H 210 −
= 0
− )pp(:H 211
0
1
2
3
4
5
A B C
t-Test: Two-Sample Assuming Unequal Variances
Low High
Mean 33.10 56.84
Variance 278.69 1047.81
1
2
3
4
5
6
A B C
t-Test: Paired Two Sample for Means
Female Male
Mean 55.68 56.40
Variance 105.64 116.75
Observations 25 25
13.195
)(:H 210 −
= 25
13.196
)pp(:H 210 −
= 0
1
2
3
4
5
A B C D
z-Test: Two Proportions
This Year 3 Years Ago
Sample Proportions 0.4351 0.3558
Observations 393 385
Sample size 5788 5154 z Critical one-tail 1.6449
13.197
D0 :H
= 0
D1 :H
0
Dry Cleaner
Doughnut shop
1
2
3
A B C D E
z-Test of the Difference Between Two Proportions (Case 1)
Sample 1 Sample 2 z Stat -4.28
1
2
3
4
5
6
A B C
t-Test: Paired Two Sample for Means
Dry C Before Dry C After
Mean 168.00 165.50
Variance 351.38 321.96
Observations 14 14
1
2
3
4
5
6
A B C
t-Test: Paired Two Sample for Means
Donut Before Donut After
Mean 308.14 295.29
Variance 809.67 812.07
Observations 14 14
Convenience store
13.198
)(:H 210 −
= 0
)(:H 211 −
> 0
Two-tail F test: F = 1.77, p-value = .0084; use unequal-variances test statistic
13.199a
)pp(:H 210 −
= 0
− )pp(:H 211
0
1
2
3
4
5
6
A B C
t-Test: Paired Two Sample for Means
Convenience Before Convenience After
Mean 374.64 348.14
Variance 2270.40 2941.82
Observations 14 14
13.200 a
)(:H 210 −
= 0
− )(:H 211
0
Two-tail F test: F = .438, p-value = .0482; use unequal-variances t-test
b
Sample size 25 25 Upper confidence limit 5.36
1
2
3
4
5
A B C D
z-Test: Two Proportions
Depressed Not Depressed
Sample Proportions 0.2879 0.2004
Observations 132 1058
1
2
3
4
5
A B C
t-Test: Two-Sample Assuming Unequal Variances
Exercise Drug
Mean 13.52 9.92
Variance 5.76 13.16
1
2
3
A B C D E F
t-Estimate of the Difference Between Two Means (Unequal-Variances)
Sample 1 Sample 2 Confidence Interval Estimate