The Greek letter used to represent the probability of a Type I error is alpha (α).
A simple aggregate index compares the sum of values in the current period to the sum
of values in a base period.
An individual can assign a subjective probability to an event based on the individual’s
knowledge about the event.
A scatter diagram is a graph that portrays the correlation between a dependent variable
and an independent variable.
Which of the following statements about stepwise regression is TRUE?
A. It only uses dependent variables and adds them one by one.
B. It uses independent variables with insignificant regression coefficients.
C. It is a step-by-step method that adds independent variables one by one in order to
build a more efficient regression equation.
D. It first selects the independent variable with the weakest correlation first.
A value that is typical or representative of the data is referred to as a measure of central
location.
Spearman’s rank-order correlation coefficient may assume a value from -1 to +1.
The Wilcoxon rank-sum test computes a z test statistic.
Percent defective charts, which are also known as p-charts or c-bar charts, show the
percent of the production that is or is not acceptable.
A pie chart shows the relative frequency in each class.
Which of the following statements is TRUE regarding the sign test?
A. It is based on the sign of the differences.
B. It is used with independent populations.
C. The chi-square is used as the test statistic.
D. The “T” statistic is the test statistic.
Local government officials are interested in knowing if taxpayers are willing to support
a school bond initiative that will require an increase in property taxes. A random sample
of 750 likely voters was taken. Four hundred fifty of those sampled favored the school
bond initiative. The 95% confidence interval for the TRUE proportion of voters
favoring the initiative is ________.
A. [0.541, 0.639]
B. [0.400, 0.600]
C. [0.500, 0.700]
D. [0.565, 0.635]
What are the critical values for a two-tailed test with a 0.01 level of significance when n
is large and the population standard deviation is known?
A. Above 1.960 and below -1.960
B. Above 1.645 and below -1.645
C. Above 2.576 and below -2.576
D. Above 1.000 and below -1.000
A stem-and-leaf display includes the following row: 5 | 10 11 31 52 79 98. Assume that
the data is rounded to the nearest whole number.
A. The frequency of the class is seven.
B. The minimum value in the class is 5.
C. The maximum value in the class is 98.
D. The class interval is 100.
A recent study of the relationship between social activity and education for a sample of
corporate executives showed the following results.
The degrees of freedom for the analysis are __________.
A. 1
B. 2
C. 3
D. 4
The following correlations were computed as part of a multiple regression analysis that
used education, job, and age to predict income.
What is this table called?
A. Net regression coefficients
B. Coefficients of nondetermination
C. Analysis of variance
D. Correlation matrix
The following correlations were computed as part of a multiple regression analysis that
used education, job, and age to predict income.
Which independent variable has the strongest association with the dependent variable?
A. Income
B. Age
C. Education
D. Job
The Pearson product-moment correlation coefficient, r, requires that variables be
measured with _____________.
A. an interval or ratio scale
B. an ordinal or ratio scale
C. a nominal or ordinal scale
D. a nominal or ratio scale
Assuming the population variances are known, the population variance of the difference
between two means is _____________.
A. The sum of the two means
B. The sum of the two population variances
C. The sum of the two population standard deviations
D. The sum of the two sample sizes for each population
The monthly amounts spent for food by families of four receiving food stamps
approximates a symmetrical, normal distribution. The sample mean is $150 and the
standard deviation is $20. Using the Empirical rule, about 95% of the monthly food
expenditures are between what two amounts?
A. $100 and $200
B. $85 and $105
C. $205 and $220
D. $110 and $190
A special-purpose aggregate price index that reflects the level of stock prices in the U.S.
market is the ______________.
A. American Stock Exchange Index
B. Consumer Confidence Index
C. Customer Satisfaction Index
D. Dow Jones Industrial Average (DJIA)
In the calculation of the arithmetic mean for grouped data, which value is used to
represent all the values in a particular class?
A. The upper limit of the class.
B. The lower limit of the class.
C. The frequency of the class.
D. The cumulative frequency preceding the class.
E. The class midpoint.
A machine is set to fill the small-size packages of M&M candies with 56 candies per
bag. A sample revealed: three bags of 56, two bags of 57, one bag of 55, and two bags
of 58. To test the hypothesis that the mean candies per bag is 56, how many degrees of
freedom are there?
A. 9
B. 1
C. 8
D. 7
If 20 out of 50 students sampled live in a college dormitory, what is the estimated
proportion of students at the University living in a dormitory?
A. 0.20
B. 0.40
C. 0.50
D. 0.60
The reported unemployment is 5.5% of the population. What measurement scale is used
to measure unemployment?
A. Nominal
B. Ordinal
C. Interval or ratio
D. Descriptive
An example of a qualitative variable is _________________.
A. Number of children in a family
B. Weight of a person
C. Color of ink in a pen
D. Miles between oil changes
Suppose a research firm conducted a survey to determine the mean amount steady
smokers spend on cigarettes during a week. A sample of 100 steady smokers revealed
that the sample mean is $20 and the sample standard deviation is $5. What is the
probability that a sample of 100 steady smokers spend between $19 and $21?
A. 0.4772
B. 0.0228
C. 0.9544
D. 1.0000
Refer to the following breakdown of responses to a survey of “Are you concerned about
being tracked while connected to the Internet?”
What is the class with the greatest frequency?
A. Very concerned
B. Somewhat concerned
C. No concern
D. None Apply
The manager of Paul’s fruit and vegetable store is considering the purchase of a new
seedless watermelon from a wholesale distributor. Since this seedless watermelon costs
$4, will sell for $7, and is highly perishable, he only expects to sell between six and
nine of them. What is the payoff value for the purchase of nine watermelons when the
demand is for seven watermelons?
A. 6
B. 13
C. 20
D. 27
The ages of all the patients in the isolation ward of the hospital are 38, 26, 13, 41, and
22. What is the population variance?
A. 106.8
B. 91.4
C. 240.3
D. 42.4
A sum of squares divided by its corresponding degrees of freedom is called a
________________.
A data set has 200 observations. In the data, a qualitative variable’s highest value is
“extremely satisfied” and its lowest value is “extremely dissatisfied.” What is the
minimum class interval that you would recommend?
A student is planning a trip home for the holidays and has three options: car, train, or
jet. The decision depends on if the weather is good or bad. In addition, the student
estimated the costs for each option. The payoff table follows.
What is the expected value of driving a car?
What are the two population parameters that specify the location and dispersion for the
sampling distribution of the mean?
Six people have declared their intentions to run for a seat on the school board in the
next local election. A poll is conducted during the campaign among 1,020 randomly
sampled voters to determine if there is any clear preference among the voters. The
responses are shown next.
What is the critical value at the 1% level of significance?
The _________ approach to probability is based on a person’s belief, opinion, or
judgment.
Given the sample information in the following table regarding public opinion on gun
control, what percent of Democrats have no opinion?
High school students were interested in a teacher’s claim that the longer the length of
time (hours) that a student studies for a test, the higher the test score. The students
collected the data and the teacher did the regression analysis with the following results.
What is the regression mean square?
The following frequency distribution shows the distribution of delivery times (in days)
for swimstuff.com customer orders during the last month.
How many orders were delivered in less than one day?
A collection of one or more basic outcomes is called a(n) _________.