Question 1

The coefficient of determination (r²)tells you

Accepted Answer

A) that the coefficient of correlation (r)is larger than 1. 
B) whether r has any significance. 
C) that you should not partition the total variation. 
D) the proportion of total variation that is explained. 
A) that the coefficient of correlation (r)is larger than 1. 
B) whether r has any significance. 
C) that you should not partition the total variation. 
D) the proportion of total variation that is explained.

Question 2

TABLE 13-6
The following Excel tables are obtained when "Score received on an exam (measured in percentage points)" (Y)is regressed on "percentage attendance" (X)for 22 students in a Statistics for Business and Economics course.
  
-Referring to Table 13-6,which of the following statements is true?

Accepted Answer

A) If attendance increases by 0.341%,the estimated mean score received will increase by 1 percentage point. 
B) If attendance increases by 1%,the estimated mean score received will increase by 39.39 percentage points. 
C) If attendance increases by 1%,the estimated mean score received will increase by 0.341 percentage points. 
D) If the score received increases by 39.39%,the estimated mean attendance will go up by 1%. 
A) If attendance increases by 0.341%,the estimated mean score received will increase by 1 percentage point. 
B) If attendance increases by 1%,the estimated mean score received will increase by 39.39 percentage points. 
C) If attendance increases by 1%,the estimated mean score received will increase by 0.341 percentage points. 
D) If the score received increases by 39.39%,the estimated mean attendance will go up by 1%.

Question 3

TABLE 13-3
The director of cooperative education at a state college wants to examine the effect of cooperative education job experience on marketability in the work place.She takes a random sample of 4 students.For these 4,she finds out how many times each had a cooperative education job and how many job offers they received upon graduation.These data are presented in the table below.  
-Referring to Table 13-3,suppose the director of cooperative education wants to construct a 95% confidence-interval estimate for the mean number of job offers received by students who have had exactly one cooperative education job.The t critical value she would use is ________.

Accepted Answer

The answer of TABLE 13-3
The director of cooperative education at...

Question 4

TABLE 13-4
The managers of a brokerage firm are interested in finding out if the number of new clients a broker brings into the firm affects the sales generated by the broker.They sample 12 brokers and determine the number of new clients they have enrolled in the last year and their sales amounts in thousands of dollars.These data are presented in the table that follows.  
-Referring to Table 13-4,the managers of the brokerage firm wanted to test the hypothesis that the number of new clients brought in had a positive impact on the amount of sales generated.The p-value of the test is ________.

Accepted Answer

< 0.005 using the Ta

Question 5

TABLE 13-3
The director of cooperative education at a state college wants to examine the effect of cooperative education job experience on marketability in the work place.She takes a random sample of 4 students.For these 4,she finds out how many times each had a cooperative education job and how many job offers they received upon graduation.These data are presented in the table below.  
-Referring to Table 13-3,suppose the director of cooperative education wants to construct a 95% confidence interval estimate for the mean number of job offers received by students who have had exactly one cooperative education job.The confidence interval is from ________ to ________.

Accepted Answer

The answer of TABLE 13-3
The director of cooperative education at...

Question 6

TABLE 13-10
The management of a chain electronic store would like to develop a model for predicting the weekly sales (in thousands of dollars)for individual stores based on the number of customers who made purchases.A random sample of 12 stores yields the following results:
  
-Referring to Table 13-10,generate the scatter plot.

Accepted Answer

The answer of TABLE 13-10
The management of a chain electronic...

Question 7

TABLE 13-13
In this era of tough economic conditions,voters increasingly ask the question: "Is the educational achievement level of students dependent on the amount of money the state in which they reside spends on education?" The partial computer output below is the result of using spending per student ($)as the independent variable and composite score which is the sum of the math,science and reading scores as the dependent variable on 35 states that participated in a study.The table includes only partial results.
  
-Referring to Table 13-13,the regression mean square (MSR)of the above regression is ________.

Accepted Answer

The answer of TABLE 13-13
In this era of tough economic...

Question 8

TABLE 13-4
The managers of a brokerage firm are interested in finding out if the number of new clients a broker brings into the firm affects the sales generated by the broker.They sample 12 brokers and determine the number of new clients they have enrolled in the last year and their sales amounts in thousands of dollars.These data are presented in the table that follows.  
-Referring to Table 13-4,the coefficient of determination is ________.

Accepted Answer

The answer of TABLE 13-4
The managers of a brokerage firm...

Question 9

The confidence interval for the mean of Y is always narrower than the prediction interval for an individual response Y given the same data set,X value,and confidence level.

Accepted Answer

A) True 
 B)False

Question 10

TABLE 13-4
The managers of a brokerage firm are interested in finding out if the number of new clients a broker brings into the firm affects the sales generated by the broker.They sample 12 brokers and determine the number of new clients they have enrolled in the last year and their sales amounts in thousands of dollars.These data are presented in the table that follows.  
-Referring to Table 13-4,the least squares estimate of the Y-intercept is ________.

Accepted Answer

The answer of TABLE 13-4
The managers of a brokerage firm...

Question 11

The standard error of the estimate is a measure of

Accepted Answer

A) total variation of the Y variable. 
B) the variation around the sample regression line. 
C) explained variation. 
D) the variation of the X variable. 
A) total variation of the Y variable. 
B) the variation around the sample regression line. 
C) explained variation. 
D) the variation of the X variable.

Question 12

TABLE 13-4
The managers of a brokerage firm are interested in finding out if the number of new clients a broker brings into the firm affects the sales generated by the broker.They sample 12 brokers and determine the number of new clients they have enrolled in the last year and their sales amounts in thousands of dollars.These data are presented in the table that follows.  
-Referring to Table 13-4,the managers of the brokerage firm wanted to test the hypothesis that the number of new clients brought in had a positive impact on the amount of sales generated.At a level of significance of 0.01,the decision that should be made implies that the number of new clients brought in ________ (had or did not have)a positive impact on the amount of sales generated.

Accepted Answer

The answer of TABLE 13-4
The managers of a brokerage firm...

Question 13

TABLE 13-10
The management of a chain electronic store would like to develop a model for predicting the weekly sales (in thousands of dollars)for individual stores based on the number of customers who made purchases.A random sample of 12 stores yields the following results:
  
-Referring to Table 13-10,the value of the F test statistic equals the square of the t test statistic when testing whether the number of customers who make purchases is a good predictor for weekly sales.

Accepted Answer

A) True 
 B)False

Question 14

The strength of the linear relationship between two numerical variables may be measured by the

Accepted Answer

A) scatter plot. 
B) coefficient of correlation. 
C) slope. 
D) Y-intercept. 
A) scatter plot. 
B) coefficient of correlation. 
C) slope. 
D) Y-intercept.

Question 15

TABLE 13-1
A large national bank charges local companies for using their services.A bank official reported the results of a regression analysis designed to predict the bank's charges (Y)measured in dollars per monthfor services rendered to local companies.One independent variable used to predict service charges to a company is the company's sales revenue (X)measured in millions of dollars.Data for 21 companies who use the bank's services were used to fit the model:
Yᵢ = β₀ + β₁Xi + Eᵢ
The results of the simple linear regression are provided below.
  
-Referring to Table 13-1,a 95% confidence interval for β₁ is (15,30).Interpret the interval.

Accepted Answer

A) You are 95% confident that the mean service charge will fall between $15 and $30 per month. 
B) You are 95% confident that the sales revenue (X)will increase between $15 and $30 million for every $1 increase in service charge (Y). 
C) You are 95% confident that mean service charge (Y)will increase between $15 and $30 for every $1 million increase in sales revenue (X). 
D) At the α = 0.05 level,there is no evidence of a linear relationship between service charge (Y)and sales revenue (X). 
A) You are 95% confident that the mean service charge will fall between $15 and $30 per month. 
B) You are 95% confident that the sales revenue (X)will increase between $15 and $30 million for every $1 increase in service charge (Y). 
C) You are 95% confident that mean service charge (Y)will increase between $15 and $30 for every $1 million increase in sales revenue (X). 
D) At the α = 0.05 level,there is no evidence of a linear relationship between service charge (Y)and sales revenue (X).

Question 16

TABLE 13-9
It is believed that,the average numbers of hours spent studying per day (HOURS)during undergraduate education should have a positive linear relationship with the starting salary (SALARY,measured in thousands of dollars per month)after graduation.Given below is the Excel output for predicting starting salary (Y)using number of hours spent studying per day (X)for a sample of 51 students.NOTE: Only partial output is shown.
   
Note: 2.051E - 05 = 2.051*10⁻⁰⁵ and 5.944E - 18 = 5.944*10⁻¹⁸.
-Referring to Table 13-9,the error sum of squares (SSE)of the above regression is

Accepted Answer

A) 1.878215. 
B) 92.0325465. 
C) 335.047257. 
D) 427.079804. 
A) 1.878215. 
B) 92.0325465. 
C) 335.047257. 
D) 427.079804.

Question 17

TABLE 13-5
The managing partner of an advertising agency believes that his company's sales are related to the industry sales.He uses Microsoft Excel to analyze the last 4 years of quarterly data (i.e.,n = 16)with the following results:
  
-Referring to Table 13-5,the value of the quantity that the least squares regression line minimizes is ________.

Accepted Answer

The answer of TABLE 13-5
The managing partner of an advertising...

Question 18

TABLE 13-12
The manager of the purchasing department of a large saving and loan organization would like to develop a model to predict the amount of time (measured in hours)it takes to record a loan application.Data are collected from a sample of 30 days,and the number of applications recorded and completion time in hours is recorded.Below is the regression output:
   
Note: 4.3946E-15 is 4.3946 ×

-Referring to Table 13-12,the p-value of the measured t test statistic to test whether the number of loan applications recorded affects the amount of time is

Accepted Answer

A) (4.3946E-15)/2. 
B) 4.3946E-15. 
C) (0.0030)/2. 
D) 0.0030. 
A) (4.3946E-15)/2. 
B) 4.3946E-15. 
C) (0.0030)/2. 
D) 0.0030.

Question 19

TABLE 13-3
The director of cooperative education at a state college wants to examine the effect of cooperative education job experience on marketability in the work place.She takes a random sample of 4 students.For these 4,she finds out how many times each had a cooperative education job and how many job offers they received upon graduation.These data are presented in the table below.  
-Referring to Table 13-3,suppose the director of cooperative education wants to construct both a 95% confidence interval estimate and a 95% prediction interval for X = 2.The confidence interval estimate would be the wider of the two intervals.

Accepted Answer

A) True 
 B)False

Question 20

TABLE 13-11
A computer software developer would like to use the number of downloads (in thousands)for the trial version of his new shareware to predict the amount of revenue (in thousands of dollars)he can make on the full version of the new shareware.Following is the output from a simple linear regression along with the residual plot and normal probability plot obtained from a data set of 30 different sharewares that he has developed:

-Referring to Table 13-11,the homoscedasticity of error assumption appears to have been violated.

Accepted Answer

A) True 
 B)False

The coefficient of determination (r²)tells you

TABLE 13-6 The following Excel tables are obtained when "Score received on an exam (measured in percentage points)" (Y)is regressed on "percentage attendance" (X)for 22 students in a Statistics for Business and Economics course. -Referring to Table 13-6,which of the following statements is true?

The confidence interval for the mean of Y is always narrower than the prediction interval for an individual response Y given the same data set,X value,and confidence level.

The standard error of the estimate is a measure of

The strength of the linear relationship between two numerical variables may be measured by the

Introduction

Organizing and Visualizing Data

Numerical Descriptive Measures

Basic Probability

Discrete Probability Distributions

The Normal Distribution and Other Continuous Distributions

Sampling and Sampling Distributions

Confidence Interval Estimation

Fundamentals of Hypothesis Testing: One-Sample Tests

Two-Sample Tests

Analysis of Variance

Chi-Square Tests and Nonparametric Tests

Introduction to Multiple Regression

Multiple Regression Model Building

Time-Series Forecasting

Statistical Applications in Quality Management

A Roadmap for Analyzing Data

Questions that Involve Online Topics

Filters

Exam 13: Simple Linear Regression

The coefficient of determination (r²)tells you

TABLE 13-6 The following Excel tables are obtained when "Score received on an exam (measured in percentage points)" (Y)is regressed on "percentage attendance" (X)for 22 students in a Statistics for Business and Economics course. -Referring to Table 13-6,which of the following statements is true?

The confidence interval for the mean of Y is always narrower than the prediction interval for an individual response Y given the same data set,X value,and confidence level.

The standard error of the estimate is a measure of

The strength of the linear relationship between two numerical variables may be measured by the

Introduction

Organizing and Visualizing Data

Numerical Descriptive Measures

Basic Probability

Discrete Probability Distributions

The Normal Distribution and Other Continuous Distributions

Sampling and Sampling Distributions

Confidence Interval Estimation

Fundamentals of Hypothesis Testing: One-Sample Tests

Two-Sample Tests

Analysis of Variance

Chi-Square Tests and Nonparametric Tests

Introduction to Multiple Regression

Multiple Regression Model Building

Time-Series Forecasting

Statistical Applications in Quality Management

A Roadmap for Analyzing Data

Questions that Involve Online Topics

Filters