Week 7 Estimation Practice
Use the GSS 2014 data on education from Chapter 5 (“The Normal Distribution”), Exercise 5.
Mean Standard Deviation N
Lower class 12.11 2.83 122
Working class 13.01 2.91 541
Middle class 14.99 2.93 475
Upper class 15.44 2.83 34
Estimation Practice
Question 1
What is the 95% confidence interval for the mean number of years of education for lower-class respondents?
1.
11.60 to 12.62
2.
23.20 to 25.24
3.
5.80 to 6.31
4.
13.60 to 14.62
2.
Question 2
What is the 95% confidence interval for the mean number of years of education for and working-class respondents?
1.
14.76 to 15.25
2.
12.76 to 13.25
3.
25.50 to 26.50
4.
6.38 to 6.63
3.
Question 3
What is the 99% confidence interval for the mean number of years of education for lower-class respondents?
1.
11.44 to 12.78
2.
5.72 to 6.39
3.
13.55 to 14.89
4.
22.88 to 25.56
4.
Question 4
What is the 99% confidence interval for the mean number of years of education for and middle-class respondents?
1.
18.65 to 19.33
2.
4.65 to 5.33
3.
7.33 to 7.67
4.
14.65 to 15.33
5.
Question 5
As our confidence in the result increases, how does the size of the confidence interval change?
1.
The confidence interval gets wider, not narrower – increasing confidence leading to less precise intervals.
2.
The confidence interval gets narrower, but not wider – decreasing confidence leading to more precise intervals.
3.
As the result increases, the confidence level remains the same.
4.
As the result increases, the confidence level is reduced.
6.
Though 70% of women with children younger than 18 years participate in the labor force, society still upholds the stay-at-home mother as the traditional model. Some believe that employment distracts mothers from their parenting role, affecting the well-being of children. In the GSS 2014, respondents were asked to indicate their level of agreement to the statement, “A working mother hurts children.” Of the 435 male respondents who answered the question, 18% strongly agreed that a working mother does not hurt children.
Question 6
What is the 90% confidence interval for this statistic for males?
1.
0.30 to 0.42
2.
0.08 to 0.11
3.
0.15 to 0.21
4.
1.50 to 2.10
7.
Question 7
Of the 566 female respondents who answered the question, 40% strongly agreed that a working mother does not hurt children. What is the 90% confidence interval for this statistic?
1.
0.74 to 0.86
2.
0.37 to 0.43
3.
0.14 to 0.18
4.
0.19 to 0.22
8.
According to a report published by the Pew Research Center in February 2010, 61% of Millennials (Americans in their teens and 20s) think that their generation has a unique and distinctive identity (N = 527).
9.
Question 8
What is the 95% confidence interval to estimate the percentage of Millennials who believe that their generation has a distinctive identity as compared with the other generations (Generation X, Baby Boomers, or the Silent Generation)?
1.
CI = 6.84 to 5.16
2.
CI = 50.88 to 60.76
3.
CI = 102.84 to 112.16
4.
CI = 56.84 to 65.16
10.
Question 9
What is the 99% confidence interval?
1.
CI = 55.53 to 66.47
2.
CI = 111.06 to 132.94
3.
CI = 27.77 to 33.24
4.
CI = 57.55 to 68.49
11.
Question 10
Are both these results compatible with the conclusion that the majority of Millennials believe that they have a unique identity that separates them from the previous generations?
1.
Yes
2.
No
