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Unformatted text preview: SOCY201—Introductory Statistics for Sociology, Fall 2009
Homework 2 (**Please answer legibly on a separate sheet**)
***Due Wednesday, September 30th***
Use SDA and the General Social Survey (GSS) or the information given to answer the following
questions:
1. The numbers in the following table represent the mean reported sexual frequency for people who are
currently married and people who have never been married 1989 to 2008.
gss year
for this
responden
t
1989
1990
1991
1993
1994
1996
1998
2000
2002
2004
2006
2008 marital status
married never married
73
77
74
72
71
77
69
73
74
65
64
66 58
59
62
63
59
64
60
64
65
65
57
65 a. Create a line plot for married and unmarried people where year is on the Xaxis and the means are
on the Yaxis.
b. Compare and contrast the trends (how average sexual frequency changes over time). What do you
notice about the trend between 2000 and 2008?
c. A friend comments that they are interested in the overall mean sexual frequency for these people—
the mean across all the years—and decides to average the means in the table. What statistical
advice should you give your friend? 2. The following table is the frequency distribution of the unemployment rate in 2005 (rounded to the one’s
place). Use this information to calculate the 1st and 10th deciles and the median (p10, p90, and p50).
Unemp Freq. Percent Cum. 2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
21 14
293
703
814
623
305
189
81
58
21
14
12
1
2
2
1 0.45
9.35
22.44
25.98
19.89
9.74
6.03
2.59
1.85
0.67
0.45
0.38
0.03
0.06
0.06
0.03 0.45
9.80
32.24
58.22
78.10
87.84
93.87
96.46
98.31
98.98
99.43
99.81
99.84
99.90
99.97
100.00 Total 3,133 100.00 3. The following grouped frequency table shows the number of burglaries per 100,000 people reported to
the police. This table is based on counties in the United States. A number like 932 means there were
932 recorded burglaries per 100,000 residents. Estimate the average burglary rate per 100,000 in
2004:
RECODE of
burg Freq. Percent Cum. 0  499
500  999
10001499
15001999
20002499
25002999 1,480
1,106
303
59
8
1 50.05
37.40
10.25
2.00
0.27
0.03 50.05
87.45
97.70
99.70
99.97
100.00 Total 2,957 100.00 4. Three confidence subscales were created that measure American confidence in their government,
spiritual/educational, and medical institutions, and the military industrial complex. The following
frequency table presents this information for respondents in 2004: Confidence Subscales
Government Spiritual/Education/ MilitaryIndustrial
Medical
0
73
14
12
1
100
61
51
2
147
152
104
3
243
249
217
4
160
185
256
5
59
137
134
6
63
54
73
845
852
847
n
a. Calculate and interpret the diversity index for the spiritual/educational/medical subscale.
b. Calculate and interpret the index of qualitative variation for the government and militaryindustrial
complex subscales. 5. The following data shows the number of people, by race, living in four Maryland counties.
Anne Arundel
411,278
White
75,009
Black
1,633
Am. Indian & Alaskan Native
14,380
Asian
446
Hawaiian/Pacific Islander Howard
190,108
43,344
681
29,503
136 Montgomery Prince George’s
630,103
234,784
151,991
559,050
3,114
3,206
122,007
33,021
633
774 Calculate and interpret the index of qualitative variation for these counties.
6. The exam scores for two sections of introductory sociology are listed below. Compute the standard
deviation for each section. Section #1: 42, 45, 56, 56, 60, 62, 67, 68, 70, 71. Section #2: 57, 57, 57,
70, 75, 77, 79, 83, 83, 92.
7. Suppose that there were two groups of people that discussed controversial political issues. Each person
rated how liberal or conservative that consider themselves to be using the following scale: extremely
liberal, liberal, slightly liberal, moderate, slightly conservative, conservative, and extremely
conservative. The scale was scored 1 through 7, liberal to conservative.
The mean for Group A was found to be 4 with a standard deviation of 0.02. The mean of Group B was
also 4, but the standard deviation was 3.5. Which group would have the more lively discussion and
why?
8. The following histogram and statistics describe the American confidence in institutions in 2008:
Confidence in American Institutions Scale: 2008
15 Percent 10 5 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Source: General Social Survey, 2008 a. Interpret the mode, median, and mean for this distribution. What do these statistics tell you about
the distribution of American confidence in institutions?
b. Interpret the following measures of dispersion: range, interquartile range, and the standard deviation.
What do these statistics tell you about the variation in the distribution of confidence?
c. Use these statistics and the histogram to write a short description of this variable. 9. Which region of the country has the most racial diversity?
a. Use the data in the following table to compare the distribution of the index of qualitative variation
for people in the Northeast, Midwest, South and West regions in 2005 by creating four box plots,
one for each region: Northeast
Midwest
South
West Low
Outlier
0.02
0.00
0.00
0.00 Low Q1 Median Q3 High 0.02
0.00
0.00
0.00 0.05
0.03
0.10
0.05 0.10
0.05
0.29
0.10 0.21
0.11
0.52
0.21 0.46
0.25
0.82
0.44 b. Describe and compare the distributions. In other words, interpret the plots.
Nota bene:
For more help on box plots go to
www.corda.com/docsource/doc7/Manuals/graph_ref/box_plot_graphs.htm High
Outlier
0.74
0.66
0.82
0.86 ...
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This note was uploaded on 10/20/2009 for the course SOCY 201 taught by Professor Staff during the Spring '08 term at Maryland.
 Spring '08
 staff

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