The annual dividend rates for a random sample of 16 companies in three different
industries, utilities, banking, and insurance were recorded. The ANOVA comparing the
mean annual dividend rate among three industries rejected the null hypothesis that the
dividend rates were equal. The mean square error (MSE) was 3.36. The following table
summarized the results:
Based on the comparison between the mean annual dividend rate for companies in the
utilities and insurance industries, _______________________.
A. a confidence interval shows that the mean annual dividend rates are not significantly
different
B. the ANOVA results show that the mean annual dividend rates are significantly
different
C. a confidence interval shows that the mean annual dividend rates are significantly
different
D. the ANOVA results show that the mean annual dividend rates are not significantly
different
Refer to the following frequency distribution on days absent during a calendar year by
employees of a manufacturing company:
How many employees were absent fewer than six days?
A. 60
B. 31
C. 91
D. 46
A recent study focused on the amount of money single men and women save monthly.
The information is summarized next. Assume that the population standard deviations
are equal.
At the .01 significance level, do women save more money than men? What is the test
statistic for this hypothesis?
A. z-statistic
B. t-statistic
C. p-statistic
D. df-statistic
An investigation of the effectiveness of a training program to improve customer
relationships included a pre-training and post-training customer survey. To compare the
differences they computed (post-training survey score – pre-training survey score).
Seven customers were randomly selected and completed both surveys. The results
follow.
For a 0.05 significance level, what is the critical value?
A. 1.943
B. 1.895
C. 1.645
D. 2.447
A quality control chart is used to monitor the customer wait time at a local call center.
Sample means of five times are averaged and plotted over time. Over the last hundred
sample means, one sample mean was outside a control limit. The process is:
A. out of control.
B. in control.
C. highly variable.
D. showing an assignable cause.
A listing of all possible outcomes of an experiment and their corresponding
probabilities of occurrence is called a ____________.
A. random variable
B. probability distribution
C. subjective probability
D. frequency distribution
A sales manager for an advertising agency believes that there is a relationship between
the number of contacts that a salesperson makes and the amount of sales dollars earned.
A regression analysis shows the following results:
What is the Y-intercept of the linear equation?
A. -12.201
B. 2.195
C. -1.860
D. 12.505
When does multicollinearity occur in a multiple regression analysis?
A. When the dependent variables are highly correlated
B. When the regression coefficients are correlated
C. When the independent variables are highly correlated
D. When the independent variables have no correlation
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. If the merchant purchases seven watermelons, the maximum opportunity
loss occurs when the demand is how many units?
A. 6
B. 7
C. 8
D. 9
In a management trainee program, 80% of the trainees are female, while 20% are male.
Ninety percent of the females attended college; 78% of the males attended college. A
management trainee is selected at random. What is the probability that the person
selected is a female who attended college?
A. 0.20
B. 0.08
C. 0.25
D. 0.72
A research firm wants to compute an interval estimate with 90% confidence for the
mean time to complete an employment test. Assuming a population standard deviation
of three hours, what is the required sample size if the error should be less than a half
hour?
A. 196
B. 98
C. 10
D. 16
Chances are 50-50 that a newborn baby will be a girl. For families with five children,
what is the probability that all the children are girls?
A. 0.900
B. 0.031
C. 0.001
D. 0.250
When the paired observations are equal in a Wilcoxon signed-rank test hypothesis:
A. observations are removed from the analysis.
B. the ranks are averaged.
C. a zero is assigned to the difference and retained in the analysis.
D. observations are removed from the analysis and “n” is not changed.
The chi-square distribution is _____________.
A. Positively skewed
B. Negatively skewed
C. Normally distributed
D. Uniformly distributed
In the Wilcoxon signed-rank test, the ranks:
A. are assigned to paired observation with a difference of zero.
B. are assigned for each sample.
C. are assigned the sign (either positive or negative) of the difference between a pair of
observations.
D. are all positive in sign.
What is the difference between a sample mean and the population mean called?
A. Standard error of the mean
B. Sampling error
C. Interval estimate
D. Point estimate
A random sample of 85 supervisors revealed that they worked an average of 6.5 years
before being promoted. The population standard deviation was 1.7 years. Using the 0.95
degree of confidence, what is the confidence interval for the population mean?
A. 6.99 and 7.99
B. 4.15 and 7.15
C. 6.14 and 6.86
D. 6.49 and 7.49
The following graph is a ____________.
A. Dot plot
B. Stem-and-leaf diagram
C. Box plot
D. Contingency table
Which of the following statements is TRUE about price-weighted indexes?
I. The Laspeyres index uses base-period quantities as weights.
II. The Paasche index tends to underweight goods whose prices have gone down.
III. The Paasche index uses current-period quantities as weights.
A. I only
B. II only
C. I and III
D. II and III
For a uniformly distributed random variable, x, P(x) = 1/(b – a).
In stratified random sampling, a population is divided into strata using naturally
occurring geographic or other boundaries. Then, strata are randomly selected and a
random sample is collected from each strata.
A large restaurant contracts with a local laundry to wash white napkins. The laundry
returns the napkins in bundles of one-hundred napkins. The restaurant randomly
samples ten napkins to make sure that the napkins are clean with no stains or other
defects. The restaurant is using a method called:
A. statistical process control.
B. fishbone analysis.
C. Pareto analysis.
D. acceptance sampling.
A new machine used in the production of motor mount bolts was put into operation.
Five samples of size 100 were randomly selected and the number of defectives in each
sample was noted.
What is the upper control limit (UCL)?
A. 6.7%
B. 7.4%
C. 8.1%
D. 100%
A company set up a kiosk in the Mall of America for several hours and asked randomly
selected people which color cell phone cover was their favorite. The results follow:
What is the probability that black or orange are the favorite colors?
To collect a sample, a population is first divided into subgroups and then a sample is
selected from each subgroup. This is called _________ sampling.
In a symmetric distribution, is the 99th percentile is located in the ________ tail.
The following data was collected comparing car prices and quantity sold (thousands).
Compute a simple aggregate index comparing car prices in 2010 to car prices in 2000.
What are the similarities and differences between the application of Chebyshev’s
theorem and the Empirical rule?
A university has 1,000 computers available for students to use. Each computer has a
250-gigabyte hard drive. The university wants to estimate the space occupied on the
hard drives. A random sample of 100 computers showed a mean of 115 gigabytes used
with a standard deviation of 20 gigabytes. What is the probability that a sample mean is
greater than 200 gigabytes?
As the sample size increases, the curve of the t-distribution approaches the
_____________________________.
A manufacturer wants to increase the shelf life of a line of cake mixes. Past records
indicate that the average shelf life of the mix is 216 days. After a revised mix has been
developed, a sample of nine boxes of cake mix had a mean of 217.222 days and a
standard deviation of 1.2019 days. At the 0.025 significance level, what is the critical
value?
For the following probability distribution:
The variance is _____________.
The ___________ method of computing index numbers has the disadvantage that the
base period quantities or weights are realistic.