A random sample of 40 companies with assets over $10 million was surveyed and
asked to indicate their industry and annual computer technology expense. The ANOVA
comparing the average computer technology expense among three industries rejected
the null hypothesis. The mean square error (MSE) was 195. The following table
summarized the results:
Based on the comparison between the mean annual computer technology expense for
companies in the tax service and food service industries, the 95% confidence interval
shows an interval of -5.85 to 14.85 for the difference. This result indicates that
_______________.
A. there is no significant difference between the two industry technology expenses
B. the interval contains a difference of 20.7
C. companies in the food service industry spend significantly more than companies in
the tax service industry
D. companies in the food service industry spend significantly less than companies in the
tax service industry
In ANOVA, the null hypothesis is:
A.
B.
C.
D.
A study by the National Park Service revealed that 50% of the vacationers going to the
Rocky Mountain region visit Yellowstone Park, 40% visit the Grand Tetons, and 35%
visit both. What is the probability that a vacationer will visit at least one of these
magnificent attractions?
A. 0.95
B. 0.35
C. 0.55
D. 0.05
Random samples of four items are selected from a manufacturing process at regular
intervals and a certain quality characteristic is measured. After 25 samples, ΣX =
15,350 and ΣR = 411.4 The measurement of quality is based on:
A. an attribute.
B. a variable.
C. a scale.
D. a chart.
A binomial distribution has 50 trials (n = 50) with a probability of success of 0.50 (Ï€ =
0.50). To use the normal distribution to approximate the binomial, what are the mean
and standard deviation?
A. = 25 and σ = 3.5355
B. = 25 and σ = 12.5
C. = 25 and σ = 4.33
D. = 50 and σ = 100
The following are the weekly amounts of welfare payments made by the federal
government to a sample of six families: $139, $136, $130, $136, $147, and $136. What
is the range?
A. $0
B. $14
C. $52
D. $17
Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to
introduce an advertising campaign to increase daily sales. In order to determine the
effectiveness of the advertising campaign a sample of 49 days of sales were taken. They
found that the average daily sales were $6,400 per day. From past history, the restaurant
knew that its population standard deviation is about $1,000. The value of the test
statistic is _______.
A. 2.8
B. 6,000
C. 6,400
D. 1.96
Using the terminology of Bayes’ theorem, a posterior probability can also be defined as:
A. a conditional probability
B. a joint probability
C. 1
D. 0
The annual commissions per salesperson employed by a retailer of mobile
communication devices averaged $40,000, with a standard deviation of $5,000. What
percent of the salespersons earn between $32,000 and $42,000?
A. 60.06%
B. 39.94%
C. 34.13%
D. 81.66%
A regression analysis yields the following information:
; n = 10; sy∙x = 1.66; ΣX = 32; ΣX2 = 134;
Compute the 95% confidence interval when X = 4.
A. 0.0, 4.05
B. 4.15, 12.25
C. 2.67, 5.33
D. 6.842, 9.497
The Intelligence Quotient (IQ) test scores for adults are normally distributed with a
mean of 100 and a standard deviation of 15. What is the probability we could select a
sample of 50 adults and find the mean of this sample is less than 95?
A. 0.0091
B. 0.9818
C. 0.4909
D. 0.9544
Refer to the following distribution:
What is the relative class frequency for the $25 up to $35 class?
A. .02
B. .04
C. .05
D. .10
The distribution of the sample statistic (H) for the Kruskal-Wallis test is approximately
equal to the:
A. F distribution.
B. t distribution.
C. chi-square distribution.
D. standard normal distribution.
A farmer who grows genetically engineered corn is experiencing trouble with corn
borers. A random check of 5,000 ears revealed the following: Many of the ears
contained no borers. Some ears had one borer; A few had two borers, and so on. The
distribution of the number of borers per ear approximated the Poisson distribution. The
farmer counted 3,500 borers in the 5,000 ears. What is the probability that an ear of
corn selected at random will contain no borers?
A. 0.3476
B. 0.4966
C. 1.000
D. 0.0631
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 slope of the linear equation?
A. -12.201
B. 2.195
C. -1.860
D. 12.505
Accounting procedures allow a business to evaluate their inventory costs based on two
methods: LIFO (Last In First Out) or FIFO (First In First Out). A manufacturer
evaluated its finished goods inventory (in $000s) for five products with the LIFO and
FIFO methods. To analyze the difference, they computed (FIFO – LIFO) for each
product. Based on the following results, does the LIFO method result in a lower cost of
inventory than the FIFO method?
What is the alternate hypothesis?
A. H1: d = 0
B. H1: d ≠0
C. H1: d ≤ 0
D. H1: d > 0
It has been hypothesized that overall academic success for college freshmen as
measured by grade point average (GPA) is a function of IQ scores, X1, hours spent
studying each week, X2, and one’s high school average, X3. Suppose the regression
equation is . The multiple standard error is 6.313 and R2 = 0.826.
Assuming other independent variables are held constant, what is the effect on GPA if
the number of hours spent studying per week increases from 32 to 36?
A local company wants to evaluate their quality of service by surveying their
customers. Their budget limits the number of surveys to 100. What is their maximum
error of the estimated mean quality for a 95% level of confidence and an estimated
standard deviation of 5?
A. 0.9604
B. 0.98
C. 1.96
D. 5%
The merchants in Dallas, Texas, suffered flood damage in May 2003. Stores were
closed for remodeling nearly two months. What is this type of variation in sales called?
A. Secular trend
B. Seasonal variation
C. Cyclical variation
D. Episodic variation
To locate the percentile for a given observation in a data set, the data must be
___________.
A. Sorted and listed from the minimum to the maximum values
B. Displayed in a histogram
C. Summarized in a frequency distribution
D. Distributed symmetrically around the mean
When expressed as a percentage, what is the range of values for multiple R2?
A. -100% to +100% inclusive
B. -100% to 0% inclusive
C. 0% to +100% inclusive
D. Unlimited range
Real income is computed by:
A. dividing money income by the CPI and multiplying by 100.
B. dividing the CPI by money income and multiplying by 100.
C. multiplying money income by the CPI.
D. subtracting the CPI from money income.
The standard deviation of any uniform probability distribution is ____________.
A. (b – a)/2
B. n(1 – Ï€)
C.
D.
A research firm conducted a survey to determine the mean amount people spend at a
popular coffee shop during a week. They found the amounts spent per week followed a
normal distribution, with a population standard deviation of $4. A sample of 49
customers revealed that the mean is $25. What is the 95% confidence interval estimate
of ?
LongLast Inc. produces car batteries. The mean life of these batteries is 60 months. The
distribution of the battery life closely follows the normal probability distribution with a
standard deviation of eight months. As a part of its testing program, LongLast tests a
sample of 25 batteries. What proportion of the samples will have a mean useful life
between 58 and 62 months?
The particular result of an experiment is called a(n) _________.
The research director of a large oil company studied the buying habits of consumers
with respect to the amount of gasoline purchased at full-service pumps. The sample
mean amount is 11.5 gallons and the median amount is 11.95 gallons. The standard
deviation of the sample is 4.5 gallons. What is Pearson’s coefficient of skewness here?
The S&P 500 is a _______________________.
If the base value is 100 and the current period value is 250, what is the index for the
current period?