In a multiple regression equation with three independent variables, X1, X2, and X3, the
interaction term is expressed as (Y)(X1).
The TRUE sampling error is usually not known because ________.
A. is unknown
B. is a random variable
C. σ2 is unknown
D. the sample mean cannot be computed
A dot plot shows the symmetry of a distribution.
In an ANOVA table, k represents the total number of sample observations and n
represents the total number of treatments.
The population variation has little or no effect in determining the size of a sample
selected from the population.
To infer something about a population, we usually take a sample from the population.
Two methods of computing a weighted price index are the Laspeyres method and
Paasche’s method.
Multiple regression analysis is used when one independent variable is used to predict
values of two or more dependent variables.
A decision maker’s course of action results in a consequence or payoff.
The midpoint of a class, which is also called a class mark, is halfway between the lower
and upper limits.
The mean of a probability distribution is called its expected value.
Quartiles divide a distribution into four equal parts.
If there are “m” ways of doing one thing, and “n” ways of doing another thing, the
multiplication formula states that there are (m) (n) ways of doing both.
The standard deviation is the positive square root of the variance.
Maximizers advocate a maximin strategy.
A survey of 25 grocery stores revealed that the average price of a gallon of milk was
$2.98, with a standard error of $0.10. What is the 98% confidence interval to estimate
the TRUE cost of a gallon of milk?
A. $2.73 to $3.23
B. $2.85 to $3.11
C. $2.94 to $3.02
D. $2.95 to $3.01
Stepwise regression analysis is also called a “backward elimination” method.
Autocorrelation is measured by the trend component of a time series.
For an ANOVA test, rejecting the null hypothesis does not identify which treatment
means differ significantly.
Percentiles divide a distribution into 100 equal parts.
For a data set with an odd number of observations that have been sorted from smallest
to largest values, where is the median located?
A. n
B. n/2
C. (n + 1)/2
D. n +
Which of the following is a point estimate for the population mean ()?
A. σ
B. x/n
C.
D. s
The trend forecast equation is Ŷ = 120 + 100t. The next forecast is for period 8. The
typical seasonal index for period 8 is 0.80. What are the forecast sales for period 8?
A. 736
B. 920
C. 800
D. 640
In a linear trend equation, which variable represents the average change in the
dependent variable for every unit change in time?
A. a
B. b
C. t
D. Ŷ
A table summarizing a set of data showing the fraction of the total number of items in
several classes is a
A. relative frequency distribution.
B. frequency distribution.
C. normal frequency distribution.
D. cumulative frequency distribution.
The sample proportion is defined as _________.
A. nπ
B. x/n
C. n!
D. π
For the third quarter, the sales are 2,500 units; the seasonal index for the quarter is 1.20.
What are the deseasonalized sales for the quarter?
A. 1,739
B. 2,520
C. 2,500
D. 2,083
The mean, as a measure of central location, would be inappropriate for which one of the
following?
A. Ages of adults at a senior citizen center
B. Incomes of lawyers
C. Number of pages in textbooks on statistics
D. Marital status of college students at a particular university
The average cost of tuition and room and board at a small private liberal arts college is
reported to be $8,500 per term, but a financial administrator believes that the average
cost is higher. A study conducted using 350 small liberal arts colleges showed that the
average cost per term is $8,745. The population standard deviation is $1,200. Let α =
0.05. What are the null and alternative hypotheses for this study?
A. H0: ≤ $9,000; H1: > $9,000
B. H0: ≥ $9,000; H1: < $9,000
C. H0: ≤ $8,500; H1: > $8,500
D. H0: ≥ $8,500; H1: < $8,500
The tread life of tires mounted on light-duty trucks follows the normal probability
distribution with a mean of 60,000 miles and a standard deviation of 4,000 miles.
Suppose you bought a set of four tires, what is the likelihood the mean tire life of these
four tires is between 57,000 and 63,000 miles?
A. 0.4332
B. 0.8664
C. 1.00
D. Very likely
The following is a Poisson probability distribution with = 0.1.
The mean of the distribution is _____.
A. 1.5
B. 0.1
C. 0.25
D. 1.0
Recently, students in a marketing research class were interested in the driving behavior
of students. Specifically, the marketing students were interested in finding out if
exceeding the speed limit was related to social activity. They collected the following
responses from 100 randomly selected students:
What is the value of the test statistic?
A. 83.67
B. 9.890
C. 50
D. 4.94
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 six watermelons when the
demand is for seven or more watermelons?
A. 18
B. 21
C. 28
D. 49
A marketing class of 50 students evaluated the instructor using the following scale:
superior, good, average, poor, and inferior. The descriptive summary showed the
following survey results: 2% superior, 8% good, 45% average, 45% poor, and 0%
inferior.
A. The instructor’s performance was great!
B. The instructor’s performance was inferior.
C. Most students rated the instructor as poor or average.
D. No conclusions can be made.
If the correlation between the two independent variables of a regression analysis is 0.11,
and each independent variable is highly correlated to the dependent variable, what does
this indicate?
A. Multicollinearity between these two independent variables.
B. A negative relationship is not possible.
C. Only one of the two independent variables will explain a high percent of the
variation.
D. An effective regression equation.
A developer of a new subdivision wants to build homes that are all different. There are
three different interior plans that can be combined with any of five different home
exteriors. How many different homes can be built?
A. 8
B. 10
C. 15
D. 30
Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches
41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that
they watch the late evening news on this local CBS station. What is the p-value?
A. 0.3461
B. 0.1539
C. 0.3078
D. 0.0100
Which one of the following is NOT a condition of the binomial distribution?
A. Independent trials
B. Only two outcomes
C. The probability of success remains constant from trial to trial
D. Sampling at least 10 trials
A minimax regret strategy will always choose the act or alternative that:
A. maximizes the expected monetary value.
B. minimizes the maximum regret or opportunity loss.
C. maximizes the potential payoff regardless of uncertainty.
D. guarantees a payoff for any state of nature.
A new machine is set or calibrated to fill tubes of toothpaste at precisely 6.75 ounces.
Then, once the machine is running, a sample of six tubes is taken every three hours and
weighed with the following results:
What is the value of the lower control factor of the range?
A. 0
B. 2.115
C. 2.004
D. 3.0
A hypothesis regarding the weight of newborn infants at a community hospital is that
the mean is 6.6 pounds. A sample of seven infants is randomly selected and their
weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. What is the
sample variance?
A. 1.177
B. 6.6
C. 1.385
D. 7.6
For hypotheses that compare two population means, what test statistic is used when the
population standard deviations are known?
A company is studying the number of daily debit card purchases. There were 20
purchases and the probability of a debit card purchase is 0.5. Based on the shape of the
distribution, approximately 99.7% of the purchases should be between _______ and
________.
For the following data, are any of the observations an outlier?
A 95% confidence interval implies that about 95 out of 100 similarly constructed
intervals will include the _____________ being estimated.
Sampling is required when crash testing cars because the products are __________.
A data set has 200 observations. In the data, a quantitative variable’s highest value is
1080 and its lowest value is 960. What is the minimum class interval that you would
recommend?
A student organization of 10 wants to select a president, a vice-president, and a
treasurer. How many different leadership assignments are possible?
You have four different strategic business plans you can select to implement against
your competitors. You estimate that the probability that the competitors are aware of
your strategies is 0.3, and 0.7 that they are unaware. The payoffs estimated for each
scenario are shown next.
What is the value of perfect information?
The weight of a bag of corn chips is normally distributed with a mean of 22 ounces and
a standard deviation of 0.5 ounces. The probability that a bag of corn chips weighs
more than 23 ounces is ____.