MATH 225N STATISTICS FINAL EXAM 2 LATEST
VERSIONS /MATH 225N WEEK 8 FINAL EXAM
QUESTIONS AND DETAILED ANSWERS|ALREADY
GRADED A+(CHAMBERLAINE UNIVERSITY)
Identify the sampling technique used in the following information.
An important part of employee compensation is a benefits package that might
include health insurance, life insurance, child care, vacation days, retirement plan,
parental leave, bonuses, etc. Suppose you want to conduct a survey of benefits
packages available in private businesses in Hawaii. You want a sample size of 100.
Sampling technique used to get the sample size of 100 is described below.
Assign each business in the Island Business Directory a number, and then use a
random-number table to select the business to be included in the sample. -
ANSWER: Simple random sample
Data may be classified by one of the four levels of measurement. What is the name
of the lowest level? - ANSWER: nominal
Identify the level of measurement corresponding to the data "Salesperson's
performance: below average, average, above average" associated with robotics. -
ANSWER: ordinal
Assume that the following data represent baseball batting averages (multiplied by
1000) for a random sample of National League players near the end of the baseball
season. Make a frequency table showing class limits, class boundaries, midpoints and
frequency. Use five classes. (Round your answer for boundaries and midpoints to the
nearest tenth.)
196 257 150 293 147 297 199 252 183
125 107 259 306 306 273 289 316 254
215 252 249 259 265 184 115 204 - ANSWER:
Class Limits Boundaries Midpoint Frequency
107-149 106.5-149.5 128.0 4
150 - 192
149.5 - 192.5
171.0
3
193 - 235
192.5 - 235.5
214.0
4
236 - 278
235.5 - 278.5
257.0
9
,279-321 278.5-321.5 300.0 6
Find the range for the following sample data.
x:
21
18
12
35
25 - ANSWER: 23
Do bonds reduce the overall risk of an investment portfolio? Let x be a random
variable representing annual percent return for the Vanguard Total Stock Index (all
Stocks). Let y be a random variable representing annual return for the Vanguard
Balanced Index (60% stock and 40% bond). For the past several years, assume the
following data.
x: 12 0 38 23 34 25
26
-12
-12
-23
y: 10
-3
27 15 24 18 15
-3
-4
-10
The sample means for x and y are 11.10 and 8.90, respectively.
Compute the coefficient of variation for each fund. Round your answers to the
nearest tenth. - ANSWER: for x-values: 193.7%, and for y-values: 146.1%
It is thought that prehistoric Indians did not take their best tools, pottery, and
household items when they visited higher elevations for their summer camps. It is
hypothesized that archaeological sites tend to lose their cultural identity and specific
cultural affiliation as the elevation of the site increases. Let x be the elevation (in
,thousands of feet) for an archaeological site in the southwestern United States. Let y
be the percentage of unidentified artifacts (no specific cultural affiliation) at a given
elevation. Suppose that the following data were obtained for a collection of
archaeological sites in New Mexico:
x
5.50
6.50
7.25
8.00
8.75
y
10
41
53
89
89
What percentage of the variation in y can be explained by the corresponding
variation in x and the least-squares line? - ANSWER: 94.8%
It is thought that prehistoric Indians did not take their best tools, pottery, and
household items when they visited higher elevations for their summer camps. It is
hypothesized that archaeological sites tend to lose their cultural identity and specific
cultural affiliation as the elevation of the site increases. Let x be the elevation (in
thousands of feet) for an archaeological site in the southwestern United States. Let y
be the percentage of unidentified artifacts (no specific cultural affiliation) at a given
elevation. Suppose that the following data were obtained for a collection of
archaeological sites in New Mexico:
x
5.75
6.00
, 7.00
8.00
9.00
y
8
10
58
53
76
At an archaeological site with elevation 8.25 (thousand feet), what does the least-
squares equation forecast for the percentage of culturally unidentified artifacts? -
ANSWER: 63.8%
It is thought that prehistoric Indians did not take their best tools, pottery, and
household items when they visited higher elevations for their summer camps. It is
hypothesized that archaeological sites tend to lose their cultural identity and specific
cultural affiliation as the elevation of the site increases. Let x be the elevation (in
thousands of feet) for an archaeological site in the southwestern United States. Let y
be the percentage of unidentified artifacts (no specific cultural affiliation) at a given
elevation. Suppose that the following data were obtained for a collection of
archaeological sites in New Mexico:
x
5.75
6.25
7.25
8.25
9.25
y
VERSIONS /MATH 225N WEEK 8 FINAL EXAM
QUESTIONS AND DETAILED ANSWERS|ALREADY
GRADED A+(CHAMBERLAINE UNIVERSITY)
Identify the sampling technique used in the following information.
An important part of employee compensation is a benefits package that might
include health insurance, life insurance, child care, vacation days, retirement plan,
parental leave, bonuses, etc. Suppose you want to conduct a survey of benefits
packages available in private businesses in Hawaii. You want a sample size of 100.
Sampling technique used to get the sample size of 100 is described below.
Assign each business in the Island Business Directory a number, and then use a
random-number table to select the business to be included in the sample. -
ANSWER: Simple random sample
Data may be classified by one of the four levels of measurement. What is the name
of the lowest level? - ANSWER: nominal
Identify the level of measurement corresponding to the data "Salesperson's
performance: below average, average, above average" associated with robotics. -
ANSWER: ordinal
Assume that the following data represent baseball batting averages (multiplied by
1000) for a random sample of National League players near the end of the baseball
season. Make a frequency table showing class limits, class boundaries, midpoints and
frequency. Use five classes. (Round your answer for boundaries and midpoints to the
nearest tenth.)
196 257 150 293 147 297 199 252 183
125 107 259 306 306 273 289 316 254
215 252 249 259 265 184 115 204 - ANSWER:
Class Limits Boundaries Midpoint Frequency
107-149 106.5-149.5 128.0 4
150 - 192
149.5 - 192.5
171.0
3
193 - 235
192.5 - 235.5
214.0
4
236 - 278
235.5 - 278.5
257.0
9
,279-321 278.5-321.5 300.0 6
Find the range for the following sample data.
x:
21
18
12
35
25 - ANSWER: 23
Do bonds reduce the overall risk of an investment portfolio? Let x be a random
variable representing annual percent return for the Vanguard Total Stock Index (all
Stocks). Let y be a random variable representing annual return for the Vanguard
Balanced Index (60% stock and 40% bond). For the past several years, assume the
following data.
x: 12 0 38 23 34 25
26
-12
-12
-23
y: 10
-3
27 15 24 18 15
-3
-4
-10
The sample means for x and y are 11.10 and 8.90, respectively.
Compute the coefficient of variation for each fund. Round your answers to the
nearest tenth. - ANSWER: for x-values: 193.7%, and for y-values: 146.1%
It is thought that prehistoric Indians did not take their best tools, pottery, and
household items when they visited higher elevations for their summer camps. It is
hypothesized that archaeological sites tend to lose their cultural identity and specific
cultural affiliation as the elevation of the site increases. Let x be the elevation (in
,thousands of feet) for an archaeological site in the southwestern United States. Let y
be the percentage of unidentified artifacts (no specific cultural affiliation) at a given
elevation. Suppose that the following data were obtained for a collection of
archaeological sites in New Mexico:
x
5.50
6.50
7.25
8.00
8.75
y
10
41
53
89
89
What percentage of the variation in y can be explained by the corresponding
variation in x and the least-squares line? - ANSWER: 94.8%
It is thought that prehistoric Indians did not take their best tools, pottery, and
household items when they visited higher elevations for their summer camps. It is
hypothesized that archaeological sites tend to lose their cultural identity and specific
cultural affiliation as the elevation of the site increases. Let x be the elevation (in
thousands of feet) for an archaeological site in the southwestern United States. Let y
be the percentage of unidentified artifacts (no specific cultural affiliation) at a given
elevation. Suppose that the following data were obtained for a collection of
archaeological sites in New Mexico:
x
5.75
6.00
, 7.00
8.00
9.00
y
8
10
58
53
76
At an archaeological site with elevation 8.25 (thousand feet), what does the least-
squares equation forecast for the percentage of culturally unidentified artifacts? -
ANSWER: 63.8%
It is thought that prehistoric Indians did not take their best tools, pottery, and
household items when they visited higher elevations for their summer camps. It is
hypothesized that archaeological sites tend to lose their cultural identity and specific
cultural affiliation as the elevation of the site increases. Let x be the elevation (in
thousands of feet) for an archaeological site in the southwestern United States. Let y
be the percentage of unidentified artifacts (no specific cultural affiliation) at a given
elevation. Suppose that the following data were obtained for a collection of
archaeological sites in New Mexico:
x
5.75
6.25
7.25
8.25
9.25
y
