The primary purpose of stratified sampling is to make the sampling process
____________.
A) more convenient
B) more economical
C) less biased
D) more accurate
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.
Which one of the following statements describes the results of the hypothesis test for the
overall regression model using α = 0.05?
A) Because the p-value is greater than alpha, we reject the null hypothesis and conclude
that there is a relationship between the dependent variable and the independent variables.
B) Because the p-value is greater than alpha, we fail to reject the null hypothesis and
conclude that there is no relationship between the dependent variable and the independent
variables.
C) Because the p-value is less than alpha, we fail to reject the null hypothesis and conclude
that there is no relationship between the dependent variable and the independent variables.
D) Because the p-value is less than alpha, we reject the null hypothesis and conclude that
there is a relationship between the dependent variable and the independent variables.
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 p-value for this hypothesis test would be between ________.
A) 0.01 and 0.02
B) 0.05 and 0.10
C) 0.10 and 0.20
D) 0.20 and 0.40
A random sample of 35 business students required an average of 50.7 minutes to
complete a statistics exam. Assume that the population standard deviation to complete
the exam was 10.4 minutes. The 95% confidence interval around this sample mean is
________.
A) (47.3, 54.1)
B) (49.8, 51.6)
C) (48.9, 52.5)
D) (45.4, 56.0)
The following table shows the number of hours that six students studied for their
statistics exam and their corresponding exam grades.
Construct a scatter plot to display this data. What conclusions can be drawn?
“Gamers” are described as people who regularly play video games. A random sample of
80 people was selected and 50 were found to be male. The 90% confidence interval for
the proportion based on this sample is ________.
A) (0.598, 0.652)
B) (0.571, 0.679)
C) (0.463, 0.787)
D) (0.536, 0.714)
The Department of Housing and Urban Development (HUD) would like to test the
hypothesis that the average size of a newly constructed house last year is different from
the average size of a newly constructed house in 2000. The following data summarizes
the sample statistics for house sizes, in square feet, for both years. Assume that the
population variances are equal.
If Population 1 is defined as homes built in 2000 and Population 2 is defined as homes
built last year, the degrees of freedom for this hypothesis test are ________.
A) 22
B) 26
C) 34
D) 36
Consider the following frequency distribution.
Which rule for constructing a frequency distribution using grouped quantitative data has
been violated?
A) Use equal-size classes.
B) Use mutually exclusive classes.
C) Avoid empty classes.
D) No rule has been violated.
AutoTrader.com would like to test if a difference exists in the age of three different
types of vehicles currently on the road–trucks, cars, and vans. The following data
represent the age of a random sample of trucks, cars, and vans.
The total sum of squares for these observations is ________.
A) 42.6
B) 48.4
C) 51.5
D) 62.0
Consider the partially completed randomized block ANOVA summary table.
The total number of observations for this ANOVA procedure is ________.
A) 22
B) 23
C) 24
D) 25
Costco sells paperback books in their retail stores and wanted to examine the
relationship between price and demand. The price of a particular novel was adjusted
each week and the weekly sales were recorded in the table below.
Management would like to use simple regression analysis to estimate weekly demand
for this novel using the price of the novel. The average weekly sales for the novel when
priced at $9 is ________.
A) 4.70
B) 5.32
C) 6.22
D) 7.56
The Central Limit Theorem requires
___________________________________________.
A) a sample size of at least 30 be used to ensure that the samples means are normally
distributed
B) the population be normally distributed to ensure that the samples means are normally
distributed
C) the bootstrap method to be used to select the sample
D) the resampling technique to be used to select the sample
Interaction between two factors can be examined using _________________ ANOVA.
A) one-way
B) randomized block
C) two-way
D) either one-way or two-way
The table below shows the number of cars sold last month by seven employees at
Concord Motors and their number of years of sales experience.
Management would like to use simple regression analysis to estimate monthly car sales
using the number of years of sales experience. The total sum of squares for this sample
is ________.
A) 53.71
B) 63.33
C) 70.83
D) 83.50
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.
Sarah would like to use simple regression analysis to estimate the number of new
clients per month based on the number of presentations made by the employee per
month. The slope for the regression equation is ________.
A) 0.1553
B) 0.3043
C) 0.5987
D) 0.8750
The Wall Street Journal reported that a recently conducted travel found that 28% of
baby boomers (those born between 1946 and 1964) took a cruise vacation within the
last three years. A random sample of 75 baby boomers was selected. What is the
probability that 23 or fewer of these individuals took a cruise within the last three
years?
A) 0.8248
B) 0.7566
C) 0.6985
D) 0.5060
Use the information below to answer the following question(s).
The following decision tree is partially completed for a company that is deciding to
build a large or small facility for a new product that will face demand that is strong or
weak. The company has an option to perform a market survey that will cost $4,000 that
will predict a strong or weak market. The payoffs for each combination of facility size
and demand are also shown.
If the company decides not to conduct the survey, the expected monetary value of
building a small facility is ________.
A) “$700
B) $3,600
C) $4,000
D) $4,600
Wells Fargo Bank would like to determine if a difference exists in the average credit
score between residents of the states of Texas, Alaska, and Iowa and also investigate if
age plays a role in credit score. The credit scores from a random sample of residents
from each state was recorded and residents were categorized as being under 40 years
old or 40 years and older. A two-way ANOVA was conducted using α = 0.05 with
Factor A assigned the state residence and Factor B assigned the age group. The results
are shown below.
The critical value for the Tukey-Kramer critical range for Factor A using α = 0.05 is
________.
A) 3.49
B) 3.61
C) 3.88
D) 4.60
Consider the partially completed randomized block ANOVA summary table.
Using α = 0.05, the critical F-score for the blocking factor for this ANOVA procedure is
________.
A) 2.901
B) 3.157
C) 3.287
D) 4.885
Entertainment Software Association would like to test if the median age of “gamers”
(those that routinely play video games) is more than 30 years old. The following table
summarizes the ages of a random sample of gamers.
Using α = 0.05, which one of the following statements is true?
A) Because the p-value is greater than α, we reject the null hypothesis and cannot
conclude that the median age of gamers is more than 30 years.
B) Because the p-value is greater than α, we fail to reject the null hypothesis and cannot
conclude that the median age of gamers is more than 30 years.
C) Because the p-value is less than α, we fail to reject the null hypothesis and conclude
that the median age of gamers is more than 30 years.
D) Because the p-value is less than α, we reject the null hypothesis and conclude that
the median age of gamers is more than 30 years.
A random sample of 17 hotels in Boston had an average nightly room rate of $165.40
with a sample standard deviation of $21.70. The 90% confidence interval around this
sample mean is ________.
A) ($144.32, $186.32)
B) ($152.22, $178.58)
C) ($156.20, $174.60)
D) ($162.76, $168.04)
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 correct
hypothesis statement for this hypothesis test would be _______________________.
A)
B)
C)
D)
A survey asked randomly selected adults 18-29 years old to indicate their working
status. The results are shown in the following table.
Calculating the probability that a randomly selected adult 18-29 years old is
unemployed is using ________ probability.
A) subjective
B) empirical
C) simple
D) classical
The number of iPhones sold today at an Apple store is an example of ________ data.
A) nominal
B) ordinal
C) interval
D) ratio
Travelocity would like to test if the standard deviation for roundtrip airfares between
New York and London is less than $200. A random sample of 22 roundtrip airfares
between New York and London had a standard deviation of $142. Using α = 0.05, the
conclusion for this hypothesis test would be that because the test statistic is
___________________.
A) more than the critical value, we can reject the null hypothesis and conclude that the
standard deviation for the roundtrip airfares between New York and London is less than
$200
B) less than the critical value, we can reject the null hypothesis and conclude that the
standard deviation for the roundtrip airfares between New York and London is less than
$200
C) less than the critical value, we fail to reject the null hypothesis and cannot conclude
that the standard deviation for the roundtrip airfares between New York and London is
less than $200
D) more than the critical value, we fail to reject the null hypothesis and cannot conclude
that the standard deviation for the roundtrip airfares between New York and London is
less than $200
A professor would like to test the hypothesis that the average number of minutes that a
student needs to complete a statistics exam has a standard deviation that is less than 5.0
minutes. A random sample of 15 students was selected and the sample standard
deviation for the time needed to complete the exam was found to be 4.0 minutes. Using
α = 0.05, the conclusion for this hypothesis test would be that because the test statistic
is ________________________.
A) more than the critical value, we fail to reject the null hypothesis and conclude that
the standard deviation for the time to complete an exam is less than 5.0 minutes
B) less than the critical value, we reject the null hypothesis and cannot conclude that the
standard deviation for the time to complete an exam is less than 5.0 minutes
C) less than the critical value, we fail to reject the null hypothesis and cannot conclude
that the standard deviation for the time to complete an exam is less than 5.0 minutes
D) more than the critical value, we fail to reject the null hypothesis and cannot conclude
that the standard deviation for the time to complete an exam is less than 5.0 minutes
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 p-value for the hypothesis test for the overall regression model is ________.
A) 0.0022
B) 0.0095
C) 0.0161
D) 0.7865
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.
Sarah would like to use simple regression analysis to estimate the number of new
clients per month based on the number of presentations made by the employee per
month. The average number of new clients per month for an employee who made 10
presentations per month is ________.
A) 1.67
B) 2.39
C) 3.05
D) 3.43
Use the information below to answer the following question(s).
Cape May Realty manages rental beach properties during the summer season for
property owners. They would like to determine if a relationship exists between the
square footage of beach property and the weekly rental rates during the summer season.
Simple regression analysis was performed using a random sample of beach properties
with the results shown below.
The size of the sample is ________.
A) 10
B) 12
C) 13
D) 14
Assume that the number of pieces of junk mail per day that a person receives in their
mail box follows the Poisson distribution and averages 4.3 pieces per day. What is the
probability that this person will receive more than two pieces of junk mail tomorrow?
A) 0.4298
B) 0.5062
C) 0.6656
D) 0.8026
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 test statistic for testing the significance of the TO variable is ________.
A) 1.07
B) 1.89
C) 3.46
D) 5.56
The data that results from a survey question that uses the Likert Scale is the ________
measurement level.
A) nominal
B) ordinal
C) interval
D) ratio
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 predicted number of wins in a season for a team that averages 7.0 penalties per game,
averages 20.0 points per game, and has a turnover differential of “5 is ________.
A) 5.86
B) 6.39
C) 8.10
D) 9.44
The ____________ criterion allows the decision maker to choose the level of risk he or
she want to assume by choosing , the index of optimism.
A) Hurwicz
B) equally likely
C) maximin
D) maximax
The purpose of inferential statistics is to summarize or display data.