Question 1

A test for the difference between two proportions can be performed using the chi- square distribution.

Accepted Answer

A) True 
 B)False

Question 2

SCENARIO 12-7
Data on the percentage of 200 hotels in each of the three large cities across the world on whether minibar charges are correctly posted at checkout are given below. $$\begin{array} { c | | c c c } 
& \text { Hong Kong } & \text { New York } & \text { Paris } \
\hline \hline \text { Yes } & 86 \% & 76 \% & 78 \% \
\text { No } & 14 \% & 24 \% & 22 \%
\end{array}$$ At the 0.05 level of significance, you want to know if there is evidence of a difference in the proportion of hotels that correctly post minibar charges among the three cities.
-Referring to Scenario 12-7, the decision made suggests that the 3 cities all have different proportions of hotels that correctly post minibar charges.

Accepted Answer

A) True 
 B)False

Question 3

SCENARIO 12-1
A corporation randomly selects 150 salespeople and finds that 66% who have never taken a self- improvement course would like such a course.The firm did a similar study 10 years ago in which
60% of a random sample of 160 salespeople wanted a self-improvement course.The groups are assumed to be independent random samples.Let  $\pi$1 and  $\pi$2 represent the true proportion of workers who would like to attend a self-improvement course in the recent study and the past study,
respectively.
-Referring to Scenario 12-1, what is the critical value when testing whether the population proportions are different if $\alpha$= 0.10?

Accepted Answer

A) $\pm$ 1.645 
B) $\pm$ 1.96 
C) 3.842 
D) 2.706 
A) $\pm$ 1.645 
B) $\pm$ 1.96 
C) 3.842 
D) 2.706

Question 4

SCENARIO 12-7
Data on the percentage of 200 hotels in each of the three large cities across the world on whether minibar charges are correctly posted at checkout are given below. $$\begin{array} { c | | c c c } 
& \text { Hong Kong } & \text { New York } & \text { Paris } \
\hline \hline \text { Yes } & 86 \% & 76 \% & 78 \% \
\text { No } & 14 \% & 24 \% & 22 \%
\end{array}$$ At the 0.05 level of significance, you want to know if there is evidence of a difference in the proportion of hotels that correctly post minibar charges among the three cities.
-Referring to Scenario 12-7, what are the values of the absolute difference and the critical range for the Marascuilo procedure to test for the difference in proportions between Hong Kong and Paris using a 0.05 level of significance?

Accepted Answer

The answer of SCENARIO 12-7
Data on the percentage of 200...

Question 5

SCENARIO 12-11
The director of admissions at a state college is interested in seeing if admissions status (admitted, waiting list, denied admission) at his college is independent of the type of community in which an applicant resides.He takes a sample of recent admissions decisions and forms the following table: $$\begin{array} { l | | c c c | c } 
& \text { Admitted } & \text { Wait List } & \text { Denied } & \text { Total } \
\hline \hline \text { Urban } & 45 & 21 & 17 & 83 \
\text { Rural } & 33 & 13 & 24 & 70 \
\text { Suburban } & 34 & 12 & 39 & 85 \
\hline \hline \text { Total } & 112 & 46 & 80 & 238
\end{array}$$ He will use this table to do a chi-square test of independence with a level of significance of 0.01.
-Referring to Scenario 12-11, the same decision would be made with this test if the level of significance had been 0.05.

Accepted Answer

A) True 
 B)False

Question 6

SCENARIO 12-12
Parents complain that children read too few storybooks and watch too much television nowadays.A survey of 1,000 children reveals the following information on average time spent watching TV and average time spent reading storybooks $$\begin{array} { | l | l | c | c | } 
\hline &  { \text { Average time spent reading story books } } \
\hline \begin{array} { l } 
\text { Average time } \
\text { spent watching } \
\text { TV }
\end{array} & \text { Less than 1 hour } & \text { Between 1 and 2 hours } & \text { More than 2 hours } \
\hline \text { Less than 2 hours } & 90 & 85 & 130 \
\hline \text { More than 2 hours } & 655 & 32 & 8 \
\hline
\end{array}$$
-Referring to Scenario 12-12, how many children in the survey spent less than 2 hours watchingTV and more than 2 hours reading story books on average?

Accepted Answer

A) 8 
B) 130 
C) 175 
D) 687 
A) 8 
B) 130 
C) 175 
D) 687

Question 7

SCENARIO 12-4
A computer used by a 24-hour banking service is supposed to randomly assign each transaction to one of 5 memory locations.A check at the end of a day's transactions gave the counts shown in the table to each of the 5 memory locations, along with the number of reported errors.
 $\begin{array} { |l |l |l |l |l |l | } 
\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline 
\end{array}$
 $$\begin{array} { | l | l | l | l | l | l | } 
\hline \text { MemorvLocation: } & 1 & 2 & 3 & 4 & 5 \
\hline \text { Number of Transactions: } & 82 & 100 & 74 & 92 & 102 \
\hline \text { Number of Reported Errors } & 11 & 12 & 6 & 9 & 10 \
\hline
\end{array}$$ The bank manager wanted to test whether the proportion of errors in transactions assigned to each of the 5 memory locations differ.
-Referring to Scenario 12-4, the critical value of the test statistic at 1% level of significance is

Accepted Answer

A) 7.7794 
B) 13.2767 
C) 20.0902 
D) 23.2093 
A) 7.7794 
B) 13.2767 
C) 20.0902 
D) 23.2093

Question 8

SCENARIO 12-4
A computer used by a 24-hour banking service is supposed to randomly assign each transaction to one of 5 memory locations.A check at the end of a day's transactions gave the counts shown in the table to each of the 5 memory locations, along with the number of reported errors.
 $\begin{array} { |l |l |l |l |l |l | } 
\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline 
\end{array}$
 $$\begin{array} { | l | l | l | l | l | l | } 
\hline \text { MemorvLocation: } & 1 & 2 & 3 & 4 & 5 \
\hline \text { Number of Transactions: } & 82 & 100 & 74 & 92 & 102 \
\hline \text { Number of Reported Errors } & 11 & 12 & 6 & 9 & 10 \
\hline
\end{array}$$ The bank manager wanted to test whether the proportion of errors in transactions assigned to each of the 5 memory locations differ.
-Referring to Scenario 12-4, the calculated value of the test statistic is

Accepted Answer

A) -0.1777 
B) -0.0185 
C) 1.2068 
D) 1.5190 
A) -0.1777 
B) -0.0185 
C) 1.2068 
D) 1.5190

Question 9

SCENARIO 12-9
Many companies use well-known celebrities as spokespersons in their TV advertisements.A study was conducted to determine whether brand awareness of female TV viewers and the gender of the spokesperson are independent.Each in a sample of 300 female TV viewers was asked to identify a product advertised by a celebrity spokesperson.The gender of the spokesperson and whether or not the viewer could identify the product was recorded.The numbers in each category are given below. $$\begin{array} { r | | c c } 
& \text { Male Celebrity } & \text { Female Celebrity } \
\hline \hline \text { Identified product } & 41 & 61 \
\text { Could not identify } & 109 & 89
\end{array}$$
-Referring to Scenario 12-9, at 5% level of significance, the conclusion is that

Accepted Answer

A) brand awareness of female TV viewers and the gender of the spokesperson are independent. 
B) brand awareness of female TV viewers and the gender of the spokesperson are not independent. 
C) brand awareness of female TV viewers and the gender of the spokesperson are related. 
D) Both (b)and (c). 
A) brand awareness of female TV viewers and the gender of the spokesperson are independent. 
B) brand awareness of female TV viewers and the gender of the spokesperson are not independent. 
C) brand awareness of female TV viewers and the gender of the spokesperson are related. 
D) Both (b)and (c).

Question 10

SCENARIO 12-8
A study was conducted to determine whether the use of seat belts in motor vehicles depends on the educational status of the parents.A sample of 792 children treated for injuries sustained from motor vehicle accidents was obtained, and each child was classified according to (1) parents' educational status (College Degree or Non-College Degree) and (2) seat belt usage (worn or not worn) during the accident.The number of children in each category is given in the table below. $$\begin{array} { r | | c c } 
& \begin{array} { c } 
\text { Non-College } \
\text { Degree }
\end{array} & \begin{array} { c } 
\text { College } \
\text { Degree }
\end{array} \
\hline \text { Seat belts not worn } & 31 & 148 \
\text { Seat belts worn } & 283 & 330
\end{array}$$
-Referring to Scenario 12-8, the calculated test statistic is

Accepted Answer

A) -0.9991 
B) -0.1368 
C) 48.1849 
D) 72.8063 
A) -0.9991 
B) -0.1368 
C) 48.1849 
D) 72.8063

Question 11

SCENARIO 12-9
Many companies use well-known celebrities as spokespersons in their TV advertisements.A study was conducted to determine whether brand awareness of female TV viewers and the gender of the spokesperson are independent.Each in a sample of 300 female TV viewers was asked to identify a product advertised by a celebrity spokesperson.The gender of the spokesperson and whether or not the viewer could identify the product was recorded.The numbers in each category are given below. $$\begin{array} { r | | c c } 
& \text { Male Celebrity } & \text { Female Celebrity } \
\hline \hline \text { Identified product } & 41 & 61 \
\text { Could not identify } & 109 & 89
\end{array}$$
-Referring to Scenario 12-9, the calculated test statistic is

Accepted Answer

A) -0.1006 
B) 0.00 
C) 5.9418 
D) 6.1194 
A) -0.1006 
B) 0.00 
C) 5.9418 
D) 6.1194

Question 12

SCENARIO 12-5
Four surgical procedures currently are used to install pacemakers.If the patient does not need to return for follow-up surgery, the operation is called a "clear" operation.A heart center wants to compare the proportion of clear operations for the 4 procedures, and collects the following numbers of patients from their own records: $$\begin{array} { c | | c c c c | | c } 
&&{ \text { Procedure } }\
&A&B&C&D   &  { \text { Total } } \
\hline \hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \
\text { Return } & 11 & 15 & 9 & 11 & 46 \
\hline \hline \text { Total } & 38 & 56 & 30 & 18 & 142
\end{array}$$
-Referring to Scenario 12-5, there is sufficient evidence to conclude that the proportions between procedure A and procedure B are different at a 0.05 level of significance.

Accepted Answer

A) True 
 B)False

Question 13

SCENARIO 12-6
According to an article in Marketing News, fewer checks are being written at the grocery store checkout than in the past.To determine whether there is a difference in the proportion of shoppers who pay by check among three consecutive years at a 0.05 level of significance, the results of a survey of 500 shoppers in three consecutive years are obtained and presented below. $$\begin{array} { | l | c | c | c | } 
\hline & & { \text { Year } } \
\hline \text { Check Written } & \text { Year 1 } & \text { Year 2 } & \text { Year 3 } \
\hline \text { Yes } & 225 & 175 & 125 \
\hline \text { No } & 275 & 325 & 375 \
\hline
\end{array}$$
-Referring to Scenario 12-6, there is insufficient evidence to conclude that the proportions between year 1 and year 3 are different at a 0.05 level of significance.

Accepted Answer

A) True 
 B)False

Question 14

SCENARIO 12-4
A computer used by a 24-hour banking service is supposed to randomly assign each transaction to one of 5 memory locations.A check at the end of a day's transactions gave the counts shown in the table to each of the 5 memory locations, along with the number of reported errors.
 $\begin{array} { |l |l |l |l |l |l | } 
\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline \quad\quad\quad&\quad&\quad&\quad&\quad&\quad\\hline 
\end{array}$
 $$\begin{array} { | l | l | l | l | l | l | } 
\hline \text { MemorvLocation: } & 1 & 2 & 3 & 4 & 5 \
\hline \text { Number of Transactions: } & 82 & 100 & 74 & 92 & 102 \
\hline \text { Number of Reported Errors } & 11 & 12 & 6 & 9 & 10 \
\hline
\end{array}$$ The bank manager wanted to test whether the proportion of errors in transactions assigned to each of the 5 memory locations differ.
-Referring to Scenario 12-4, which test would be used to properly analyze the data in this experiment?

Accepted Answer

A)  $x ^ { 2 }$ test of independence 
B)  $x ^ { 2 }$ test for difference among more than two proportions 
C) Wilcoxon rank sum test 
D) Kruskal-Wallis rank Test 
A)  $x ^ { 2 }$ test of independence 
B)  $x ^ { 2 }$ test for difference among more than two proportions 
C) Wilcoxon rank sum test 
D) Kruskal-Wallis rank Test

Question 15

SCENARIO 12-6
According to an article in Marketing News, fewer checks are being written at the grocery store checkout than in the past.To determine whether there is a difference in the proportion of shoppers who pay by check among three consecutive years at a 0.05 level of significance, the results of a survey of 500 shoppers in three consecutive years are obtained and presented below. $$\begin{array} { | l | c | c | c | } 
\hline & & { \text { Year } } \
\hline \text { Check Written } & \text { Year 1 } & \text { Year 2 } & \text { Year 3 } \
\hline \text { Yes } & 225 & 175 & 125 \
\hline \text { No } & 275 & 325 & 375 \
\hline
\end{array}$$
-Referring to Scenario 12-6, what is the correct conclusion?

Accepted Answer

A) There is enough evidence that the proportions are all different in the 3 years. 
B) There is not enough evidence that the proportions are all different in the 3 years. 
C) There is enough evidence that at least two of the proportions are not equal. 
D) There is not enough evidence that at least two of the proportions are not equal. 
A) There is enough evidence that the proportions are all different in the 3 years. 
B) There is not enough evidence that the proportions are all different in the 3 years. 
C) There is enough evidence that at least two of the proportions are not equal. 
D) There is not enough evidence that at least two of the proportions are not equal.

Question 16

SCENARIO 12-11
The director of admissions at a state college is interested in seeing if admissions status (admitted, waiting list, denied admission) at his college is independent of the type of community in which an applicant resides.He takes a sample of recent admissions decisions and forms the following table: $$\begin{array} { l | | c c c | c } 
& \text { Admitted } & \text { Wait List } & \text { Denied } & \text { Total } \
\hline \hline \text { Urban } & 45 & 21 & 17 & 83 \
\text { Rural } & 33 & 13 & 24 & 70 \
\text { Suburban } & 34 & 12 & 39 & 85 \
\hline \hline \text { Total } & 112 & 46 & 80 & 238
\end{array}$$ He will use this table to do a chi-square test of independence with a level of significance of 0.01.
-Referring to Scenario 12-11, the null hypothesis will be rejected.

Accepted Answer

A) True 
 B)False

Question 17

SCENARIO 12-5
Four surgical procedures currently are used to install pacemakers.If the patient does not need to return for follow-up surgery, the operation is called a "clear" operation.A heart center wants to compare the proportion of clear operations for the 4 procedures, and collects the following numbers of patients from their own records: $$\begin{array} { c | | c c c c | | c } 
&&{ \text { Procedure } }\
&A&B&C&D   &  { \text { Total } } \
\hline \hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \
\text { Return } & 11 & 15 & 9 & 11 & 46 \
\hline \hline \text { Total } & 38 & 56 & 30 & 18 & 142
\end{array}$$
-Referring to Scenario 12-5, what is the value of the critical range for the Marascuilo procedure to test for the difference in proportions between procedure A and procedure B using a 0.05 level of significance?

Accepted Answer

The answer of SCENARIO 12-5
Four surgical procedures currently are used...

Question 18

SCENARIO 12-11
The director of admissions at a state college is interested in seeing if admissions status (admitted, waiting list, denied admission) at his college is independent of the type of community in which an applicant resides.He takes a sample of recent admissions decisions and forms the following table: $$\begin{array} { l | | c c c | c } 
& \text { Admitted } & \text { Wait List } & \text { Denied } & \text { Total } \
\hline \hline \text { Urban } & 45 & 21 & 17 & 83 \
\text { Rural } & 33 & 13 & 24 & 70 \
\text { Suburban } & 34 & 12 & 39 & 85 \
\hline \hline \text { Total } & 112 & 46 & 80 & 238
\end{array}$$ He will use this table to do a chi-square test of independence with a level of significance of 0.01.
-Referring to Scenario 12-11, the same decision would be made with this test if the level of significance had been 0.005.

Accepted Answer

A) True 
 B)False

Question 19

SCENARIO 12-12
Parents complain that children read too few storybooks and watch too much television nowadays.A survey of 1,000 children reveals the following information on average time spent watching TV and average time spent reading storybooks $$\begin{array} { | l | l | c | c | } 
\hline &  { \text { Average time spent reading story books } } \
\hline \begin{array} { l } 
\text { Average time } \
\text { spent watching } \
\text { TV }
\end{array} & \text { Less than 1 hour } & \text { Between 1 and 2 hours } & \text { More than 2 hours } \
\hline \text { Less than 2 hours } & 90 & 85 & 130 \
\hline \text { More than 2 hours } & 655 & 32 & 8 \
\hline
\end{array}$$
-Referring to Scenario 12-12, how many children in the survey spent less than 2 hours watchingTV and no more than 2 hours reading storybooks on average?

Accepted Answer

A) 8 
B) 130 
C) 175 
D) 687 
A) 8 
B) 130 
C) 175 
D) 687

Question 20

SCENARIO 12-3
The director of transportation of a large company is interested in the usage of her van pool.She considers her routes to be divided into local and non-local.She is particularly interested in learning if there is a difference in the proportion of males and females who use the local routes.She takes a sample of a day's riders and finds the following: $$\begin{array} { l | | c c | c } 
& \text { Male } & \text { Female } & \text { Total } \
\hline \hline \text { Local } & 27 & 44 & 71 \
\text { Non-Local } & 33 & 25 & 58 \
\hline \hline \text { Total } & 60 & 69 & 129
\end{array}$$ She will use this information to perform a chi-square hypothesis test using a level of significance of 0.05.
-Referring to Scenario 12-3, the expected cell frequency in the Female/Non-Local cell is.

Accepted Answer

The answer of SCENARIO 12-3
The director of transportation of a...

A test for the difference between two proportions can be performed using the chi- square distribution.

Defining and Collecting Data

Organizing and Visualizing Variables

Numerical Descriptive Measures

Basic Probability

Discrete Probability Distributions

The Normal Distribution

Sampling Distributions

Confidence Interval Estimation

Fundamentals of Hypothesis Testing: One-Sample Tests

Two-Sample Tests

Simple Linear Regression

Multiple Regression

Business Analytics

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Exam 11: Chi-Square Tests

A test for the difference between two proportions can be performed using the chi- square distribution.

Defining and Collecting Data

Organizing and Visualizing Variables

Numerical Descriptive Measures

Basic Probability

Discrete Probability Distributions

The Normal Distribution

Sampling Distributions

Confidence Interval Estimation

Fundamentals of Hypothesis Testing: One-Sample Tests

Two-Sample Tests

Simple Linear Regression

Multiple Regression

Business Analytics

Filters