During the 2013 Major League Baseball season, the St. Louis Cardinals averaged
41,602 fans per home game. Suppose attendance during the season follows the normal
probability distribution with a standard deviation of 9,440 per game. The interval
around the mean that contains 95% of the attendance is ________.
A) 3,842, 79,362
B) 13,282, 69,922
C) 18,002, 65,202
D) 22,722, 60,482
A manufacturer of smartphone batteries will randomly select 20 batteries from the
process each day and count the number of defects. Historically, 4% of the batteries
produced by this company have been defective. The following data represent the
frequency of defective batteries from a random sample of 200 days.
The manufacturer would like to test if the probability distribution for defective batteries
follows the binomial distribution with p = 0.04 and n = 20 using α = 0.05. The test
statistic for this sample is ________.
A) 4.974
B) 5.335
C) 8.017
D) 10.359
Use the following information to answer the question(s) below.
The National Football League has developed a regression model to predict the number
of wins during a season for a team using the following independent variables:
•Average points per game during the season (PPG)
•Average number of penalties committed per game during the season (PEN)
•Turnover differential during the season (TO)
Turnover differential is defined as the number of times the team took the ball away from
their opponent with a turnover minus the number of times the team gave the ball away to
their opponent with a turnover. For example, if TO = +5, the team had five more
takeaways than giveaways. If TO = “7, the team had seven more giveaways than
takeaways during the season.
The following Excel output shows the partially completed regression output from a
random season.
Every additional turnover differential per season will ___________________________.
A) decrease the average number of wins per season by 1.5572
B) decrease the average number of wins per season by 0.1371
C) increase the average number of wins per season by 1.5572
D) increase the average number of wins per season by 0.1371
The National Basketball Association (NBA) would like to develop a multiple regression
model that would predict the number of wins for a team during the season. The
following table shows the variance inflation factors for the independent variables
turnovers per game (TO), rebounds per game (REB), assists per game (ASSISTS), and
steals per game (STEALS).
Which one of the following statements is true?
A) There is no multicollinearity present in this multiple regression model.
B) To eliminate multicollinearity, the variable TO should be removed from this model.
C) To eliminate multicollinearity, the variables TO and REB should be removed from
this model.
D) To eliminate multicollinearity, the variable STEALS should be removed from this
model.
Entertainment Software Association would like to test if the standard deviation for the
age of “gamers” (those that routinely play video games) is equal to 6.0 years. The
standard deviation for the age from a random sample of 24 gamers is 3.8 years. Using α
= 0.05, the upper critical value for this hypothesis test would be ________.
A) 26.789
B) 31.960
C) 38.076
D) 41.144
Consider the partially completed two-way ANOVA summary table.
The Factor A test statistic for this ANOVA procedure is ________.
A) 2.36
B) 4.18
C) 6.25
D) 7.55
The Dean of the Business School at City University would like to test the hypothesis
that a difference exists between the median final exam grades for the Introduction to
Marketing course and the Introduction to Finance course. A random sample of eight
students who took both courses was selected and their final exam grade for each course
is shown below.
The appropriate nonparametric procedure for this analysis is the _________________
test.
A) Wilcoxon signed-rank
B) Kruskal-Wallis
C) Wilcoxon rank-sum
D) sign
Assume that the average talk time on an Apple iPhone is 20 hours and that this time
follows the exponential probability distribution. What is the probability that a randomly
selected iPhone will experience less than 15 hours of talk time?
A) 0.2555
B) 0.3184
C) 0.4252
D) 0.5276
YouTube would like to test the hypothesis that the average length of an online video
watched by a user is more than 8 minutes. A random sample of 37 people watched
online videos that averaged 8.7 minutes in length. It is believed that the population
standard deviation for the length of online videos is 2.5 minutes. YouTube would like to
set α = 0.02. The test statistic for this hypothesis test would be ________.
A)
B)
C)
D)
Sarah is the office manager for a group of financial advisors who provide financial
services for individual clients. She would like to investigate whether a relationship
exists between the number of presentations made to prospective clients in a month and
the number of new clients per month. The following table shows the number of
presentations and corresponding new clients for a random sample of six employees.
The test statistic for testing whether the population correlation coefficient is not equal to
zero is ________.
A) 0.84
B) 1.20
C) 1.77
D) 2.36
The Central Limit Theorem plays an important role in statistics because it provides
information about the shape of the
________________________________________________.
A) population distribution when the sample size is sufficiently large
B) sampling distribution when the sample size is sufficiently large
C) population distribution for any sample size
D) sampling distribution for any sample size
The federal government would like to test the hypothesis that the average age of men
filing for Social Security is higher than the average age of women set using α = 0.05
with the following data:
Which one of the following statements is true? Because the p-value is
___________________________________________________________.
A) greater than α, we fail to reject the null hypothesis and can conclude that the average
age of men filling for social security is more than the average age of women
B) greater than α, we fail to reject the null hypothesis and cannot conclude that the
average age of men filling for social security is more than the average age of women
C) less than α, we fail to reject the null hypothesis and conclude that the average age of
men filling for social security is more than the average age of women
D) less than α, we reject the null hypothesis and cannot conclude that the average age of
men filling for social security is less than the average age of women
The Department of Transportation would like to test the hypothesis that the average age
of cars on the road is less than 12 years. A random sample of 45 cars had an average age
of 10.6 years. It is believed that the population standard deviation for the age of cars is
4.1 years. The Department of Transportation would like to set α = 0.05. The critical
value for this hypothesis test would be ________.
A) 1.28
B) 1.645
C) 2.575
D) 1.96
The following data represents the actual talk time, in hours, for the Samsung
smartphone for 11 users.
What percentile is the talk time of 21.6 hours?
A) 41st
B) 49th
C) 54th
D) 58th
Susan would like to conduct a survey of homeowners in the Meadowbrook
neighborhood to get their opinions on proposed road modifications in the area. Which
of the following is an example of a systematic sample?
A) Susan randomly chooses two streets in the neighborhood and selects every home on
these streets.
B) Susan selects the first 20 homes that she passes as she walks into the entrance of the
neighborhood.
C) Susan selects every third house on each street in the neighborhood.
D) Susan ensures that her sample contains an equal number of two-story, split-level,
and ranch homes in her sample
The Dean of the Business School at State University would like to test the hypothesis
that no difference exists between the average final exam grades for the Introduction to
Marketing course and the Introduction to Finance course. A random sample of eight
students who took both courses was selected and their final exam grades for each
course are shown below.
If Population 1 is defined as the Marketing exam scores and Population 2 is defined as
the Finance exam scores, the degrees of freedom for this hypothesis test are ________.
A) 5
B) 6
C) 7
D) 8
Susan would like to conduct a survey of homeowners in the Meadowbrook
neighborhood to get their opinions on proposed road modifications in the area. Which
of the following is an example of a cluster sample?
A) Susan randomly chooses two streets in the neighborhood and selects every home on
these streets.
B) Susan selects the first 20 homes that she passes as she walks into the entrance of the
neighborhood.
C) Susan selects every third house on each street in the neighborhood.
D) None of these choices describes a cluster sample.
Use the following information to answer the question(s) below.
A home appraisal company would like to develop a regression model that would predict
the selling price of a house based on the age of the house in years (Age), the living area
of the house in square feet (Living Area) and the number of bedrooms (Bedrooms). The
following Excel output shows the partially completed regression output from a random
sample of homes that have recently sold.
The F-test statistic for the overall regression model is ________.
A) 5.263
B) 8.117
C) 8.864
D) 9.437
Deanna has been hired to visit the local shopping mall to conduct a survey about the
upcoming political election. She needs to select respondents at the mall and ask them
questions about their voting tendencies. Deanna decides to position herself by the only
entrance to the mall and select every 10th shopper entering the mall to participate.
Which of the following sampling techniques best describes Deanna’s method?
A) cluster
B) probability
C) simple random
D) systematic
Use the following information to answer the question(s) below.
The National Football League has developed a regression model to predict the number
of wins during a season for a team using the following independent variables:
•Average points per game during the season (PPG)
•Average number of penalties committed per game during the season (PEN)
•Turnover differential during the season (TO)
Turnover differential is defined as the number of times the team took the ball away from
their opponent with a turnover minus the number of times the team gave the ball away to
their opponent with a turnover. For example, if TO = +5, the team had five more
takeaways than giveaways. If TO = “7, the team had seven more giveaways than
takeaways during the season.
The following Excel output shows the partially completed regression output from a
random season.
The 95% prediction interval for the number of wins per season for a specific team that
averages 260 passing yards per game, 90 rushing yards per game and averages 25 points
per game is ___________.
A) (5.15, 13.27)
B) (2.50, 15.92)
C) (6.12, 12.30)
D) (6.95, 11.46)
Which of the following is an example of qualitative data?
A) today’s high temperature
B) the class average of your last statistics exam
C) the amount of time that you studied for your last statistics exam
D) your last name
Consumer Reports would like to conduct a hypothesis test to determine if the average
battery life for an iPad is different from the average battery life for a Kindle Fire. The
following data represents the battery life from a random sample of iPads and Kindle
Fires in hours. Assume that the population variances are equal.
Define Population 1 as iPads and Population 2 as Kindles and use the p-value approach
to test this hypothesis with α = 0.02.
The following table displays the amount of data that Steve has used each month, in GB,
with his iPhone during the past six months.
The predicted data usage for Month 7 using trend projection is ________.
A) 10.0 GB
B) 10.4 GB
C) 11.1 GB
D) 12.4 GB
State University offers several sections of a Business Statistics course in an in-class and
online format. Both formats are administered the same final exam each year. You have
been assigned to test the hypothesis that the average final exam score of in-class
students is different from the average final exam score of online students. The following
data summarizes the sample statistics for the final exam scores for students from each
format. Assume that the population variances are unequal.
If Population 1 is defined as in-class format and Population 2 is defined as online
format, the test statistic for this hypothesis test would be ________.
A)
B)
C)
D)
A ________ represents the width of the confidence interval between a sample mean and
its upper limit or between a sample mean and its lower limit.
A) margin of error
B) confidence level
C) significance level
D) confidence interval
The following distribution shows the frequency of daily revenue for an Italian
restaurant in Wilmington, Delaware.
What is the probability that a randomly selected day will generate under $2,000 in
revenue?
A) 0.050
B) 0.160
C) 0.225
D) 0.500
Consider the partially completed one-way ANOVA summary table.
The number of populations being compared for this ANOVA procedure is ____.
A) 2.
B) 3.
C) 4.
D) 5.
Chris is employed by Silver Lake Resort in Orlando, Florida, and sells timeshares. The
following table shows the number of timeshare sales for Chris for each quarter over the
past three years.
The following dummy variables were created:
The regression results (with only the significant variables included) are shown in the
table below.
The sales forecast Period 13 using this model is ________.
A) 10.6
B) 11.1
C) 11.8
D) 13.0
CoStar would like to test if the vacancy rate for “warehouse” stores is more than 8%. A
Type II error would occur if CoStar concludes that the vacancy rate was
_______________________.
A) more than 8% when, in reality, the proportion was 8% or less
B) 8% or less when, in reality, the proportion was more than 8%
C) equal to 8% when, in reality, the proportion was 8% or less
D) not equal to 8% when, in reality, the proportion was equal to 8%
General stepwise regression uses the Cp statistic, which measures the difference
between the true population model and the regression model derived from the sample
data.
Travelocity would like to test if the average roundtrip airfare between New York and
London is less than $1,400. A Type II error would occur if Travelocity concludes that
the average airfare is _______________________________________________.
A) equal to $1,400 when, in reality, the average airfare is not equal $1,400 or more
B) not equal to $1,400 when, in reality, the average airfare is equal to $1,400
C) $1,400 or more when, in reality, the average airfare is less than $1,400
D) less than $1,400 when, in reality, the average airfare is $1,400 or more
Use the following information to answer the question(s) below.
Ford would like to develop a regression model that would predict the number of cars
sold per month by a dealership employee based on the employee’s number of years of
sales experience (Exp), the employee’s weekly base salary before commissions (Salary),
and the education level of the employee. There are three levels of education in the sales
forcehigh school degree, associate’s degree, and bachelor’s degree. The following
dummy variables have been defined.
The following Excel output shows the partially completed regression output from a
random sample of employees from the previous month.
The 95% confidence interval for the regression coefficient for the Exp variable is
________.
A) (-0.461, 0.939)
B) (-0.022, 0.501)
C) (0.039, 0.439)
D) (0.139, 0.339)