Inquiries arrive at a record message device according to a Poisson process of rate 15
inquiries per minute. The probability that it takes more than 12 seconds for the first
inquiry to arrive is approximately _________
a) 0.05
b) 0.75
c) 0.25
d) 0.27
e) 0.73
The following graphic of residential housing data (selling price and size in square feet)
indicates _____________.
a) an inverse relation between the
two variables
b) no relation between the two
variables
c) a direct relation between the two
variables
d) a negative exponential relation between the two variables
e) a sinusoidal relationship between the two variables
Nels Neugent, Purchasing Manager at Mid-West Medical Center, is designing a p chart
to monitor the proportion of defective purchase orders issued at Mid-West. He has the
proportions defective for 22 samples of purchase orders. Each sample contains 150
purchase orders, and the average proportion defective is 0.08. The upper control limit
for Nels’s p chart is ___________.
a) 0.1736
b) 0.1465
c) 0.1312
d) 0.0940
e) 0.1845
A cancer research group was interested in determining the percentage of women 40
years or older that have regularly scheduled mammograms. To accomplish this, they
surveyed 500 women in this age group and based on 155 women that responded
affirmatively, estimated the percentage of all women in this age group that have
regularly scheduled mammograms. This process is an example of _________
a) nonparametric statistics
b) nominal data
c) descriptive statistics
d) inferential statistics
e) census
A researcher believes that arrivals at a walk-in hair salon are Poisson distributed. The
following data represent a distribution of frequency of arrivals in a one hour time
period.
Using
= 0.10, the critical chi-square value for this goodness-of-fit test is _______.
a) 1.064
b) 13.277
c) 9.236
d) 8.799
e) 7.779
BigShots, Inc. is a specialty e-tailer that operates 87 catalog Web sites on the Internet.
Kevin Conn, Sales Director, feels that the style (color scheme, graphics, fonts, etc.) of a
Web site may affect its sales. He chooses three levels of design style (neon, old world
and sophisticated) and randomly assigns six catalog Web sites to each design style. In
Kevin’s experiment “style” is _______.
a) the dependent variable
b) a treatment variable
c) a concomitant variable
d) a blocking variable
e) a response variable
On discovering an improperly adjusted drill press, Jack Joyner, Director of Quality
Control, ordered a 100% inspection of all castings drilled during the evening shift. Jack
is ordering a ___________________.
a) statistic from the castings
b) census of the castings
c) sample of the castings
d) sorting of the castings
e) parameter of the castings
A multiple regression analysis produced the following tables.
These results indicate that ____________.
a) none of the predictor variables are significant at the 5% level
b) each predictor variable is significant at the 5% level
c) x1is the only predictor variable significant at the 5% level
d) x2is the only predictor variable significant at the 5% level
e) all variables are significant at 5% level
Suppose the population of all public Universities shows the annual parking fee per
student is $110 with a standard deviation of $18. If a random sample of size 49 is drawn
from the population, the probability of drawing a sample with a mean of less than $92 is
_______.
a) 0.3400
b) 0.1600
c) 0.0000
d) 1.0000
e) 0.7000
A company believes that it controls more than 30% of the total market share for one of
its products. To prove this belief, a random sample of 144 purchases of this product is
contacted. It is found that 50 of the 144 purchased this company’s brand of the product.
If a researcher wants to conduct a statistical test for this problem, the test would be
_______.
a) a one-tailed test
b) a two-tailed test
c) an alpha test
d) a finite population test
e) a finite sample test
Ray Crofford is evaluating investment alternatives for the $100,000 which he inherited
from his grandfather. His investment advisor has identified four alternatives and
constructed the following table which shows expected profits (in $10,000’s) for various
market conditions and their probabilities.
If Ray uses the EMV criterion, the appropriate choice is ________.
a) T-Bills
b) Stocks
c) Bonds
d) Mixture
e) Bank CD’s
Jim Royo, manager of Billings Building Supply (BBS), wants to develop a model to
forecast BBS’s monthly sales (in $1,000’s). He selects the dollar value of residential
building permits (in $10,000) as the predictor variable. An analysis of the data yielded
the following tables.
Using
= 0.05 the critical value of the Durbin-Watson statistic, dU,is _________.
a) 1.54
b) 1.42
c) 1.43
d) 1.44
e) 1.85
A local pediatrician office is interested in the “no-show” appointment count for each of
the 4 pediatricians. “No-show” appointments represent lost revenues because the
physician is idle when patients do not show for their scheduled appointments. Using the
data in the table below and an alpha of .10, what is the null hypothesis?
a) The physicians differ in the no-show rates.
b) The no show rates differ by day of week
c) The no show rate between physician is equal
d) The no show rate between days of the week is equal
e) The no show rates are dependent upon both day of week and physician.
According to the central limit theorem, for samples of size 64 drawn from a population
with µ = 800 and = 56, the standard deviation of the sampling distribution
of sample means would equal _______.
a) 7
b) 8
c) 100
d) 800
e) 80
Dorothy Little purchased a mailing list of 2,000 names and addresses for her mail order
business, but after scanning the list she doubts the authenticity of the list. She randomly
selects five names from the list for validation. If 40% of the names on the list are
non-authentic, and x is the number on non-authentic names in her sample, the expected
(average) value of x is ______________.
a) 2.50
b) 2.00
c) 1.50
d) 1.25
e) 1.35
Collinsville Construction Company purchases steel rods for its projects. Based on
previous tests, Claude Carter, Quality Assurance Manager, has recommended
purchasing rods from Redding Rods, Inc. (population 1), rather than Stockton Steel
(population 2), since Redding’s rods had less variability in length. Recently, Stockton
revised it rod shearing operation, and Claude has sampled the outputs from Redding’s
and Stockton’s rod manufacturing processes. The results for Redding were s1
2= 0.10
with n1= 8, and, for Stockton, the results were s2
2= 0.05 with n2= 10. Assume that rod
lengths are normally distributed in the population. Claude’s alternative hypothesis is
_____________.
a)
b)
c)
d)
e) s s
Paige DeMarco is the Vice President for University Advancement at State University.
She is responsible for the capital campaign to raise money for the new student services
building. Paige plans to target alumni and acquires her sampling frame from the State
University Office of Alumni Relations. She intends to contact these individuals
regarding possible donations. Paige chooses her sample by selecting six-digit numbers
(1 to 150,000) from a random number table. Her sample is a _________.
a) simple random sample
b) stratified sample
c) systematic sample
d) convenience sample
e) cluster sample
A gasoline distributor wonders whether an individual’s income level influences the
grade of gasoline purchased. The following is a contingency table from a random
sample of 300 individuals.
Using
= .05, critical chi-square value is ______________.
a) 15.09
b) 5.99
c) 9.21
d) 16.81
e) 23.87
A statistics student made the following grades on 7 tests: 76, 82, 92, 95, 79, 86, and 92.
What is the mode?
a) 79
b) 82
c) 86
d) 92
e) 76
Completion time (from start to finish) of a building remodeling project is normally
distributed with a mean of 200 work-days and a standard deviation of 10 work-days. To
be 99% sure that we will not be late in completing the project, we should request a
completion time of _______ work-days.
a) 211
b) 207
c) 223
d) 200
e) 250
Annie Mikhail, market analyst for a national company specializing in historic city tours,
is analyzing the relationship between the sales revenue from historic city tours and the
size of the city. She gathers data from six cities in which the tours are offered. Annie’s
dependent variable is annual sales revenues and her independent variable is the city
population. Regression analysis of the data yielded the following tables.
For a city with a population of 500,000, Annie’s model predicts annual sales of
________________.
a) $70,780
b) $5,259
c) $170,780
d) $52,597
e) $152,597
A suburban realtor is studying commuter time in the Houston metropolitan area. She
has been told the average weekday travel time from a southern suburb at 8:00am is 45
minutes. For five months she counts the number of days that it takes her more than 45
minutes to arrive in downtown when she leaves her house at 8:00am. She expects the
data are uniformly distributed across the five months. Her sample of observed data
yields the following frequencies 9 days, 15 days, 8 days, 11 days, 12 days. Using
= .
10, the appropriate decision is _______.
a) do not reject the null hypothesis that the observed distribution is uniform
b) do not reject the null hypothesis that the observed distribution is not uniform
c) reject the null hypothesis that the observed distribution is uniform
d) reject the null hypothesis that the observed distribution is not uniform
e) do nothing
The nonparametric alternative to analysis of variance for a randomized block design is
the _______.
a) chi-square test
b) Kruskal-Wallis test
c) Mann-Whitney U test
d) Wilcoxon test
e) Friedman test
An instructor is evaluating the performance of students on a test. He records the number
of points that each student missed and created a frequency distribution. This is provided
below:
What is the mean number of points missed?
a) 20
b) 25
c) 29
d) 30
e) 35
A manager was asked to rate the performance of his employees on a scale of 1 to 6. A 1
means that the performance is awful while a 6 means that it is excellent. The
measurement level of this data is _______.
a) interval level data
b) ordinal level data
c) nominal level data
d) ratio level data
e) relative level data
Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities
in the payroll system and orders an inspection of “each and every payroll voucher
issued since January 1, 2000.” Each payroll voucher was inspected and the following
frequency distribution was compiled.
The cumulative frequency of the second class interval is _________.
a) 1,500
b) 500
c) 900
d) 1,000
e) 1,200
Shaun Connor, Human Resources Manager forAmerican Oil Terminals (AOT), is
reviewing the operator training hours at AOT nationally. His staff compiled the
following table of national statistics on operators training hours.
What can Shaun conclude from these statistics?
a) The East Coast distribution is skewed to the left.
b) The East Coast distribution is skewed to the right.
c) The West Coast distribution is skewed to the left.
d) The West Coast distribution is skewed to the right.
e) Both distributions are symmetrical.
Cindy Ho, VP of Finance at Discrete Components, Inc. (DCI), theorizes that the
discount level offered to credit customers affects the average collection period on credit
sales. Accordingly, she has designed an experiment to test her theory using four sales
discount rates (0%, 2%, 4%, and 6%) by randomly assigning five customers to each
sales discount rate. Cindy’s null hypothesis is ______.
a)
1
2
3
4
5
b)
1
2
3
4
5
c)
1
2
3
4
d)
1
2
3
4
e)
1≠
2
3
4
A local parent group was concerned with the increasing school cost for families with
school aged children. The parent group was interested in understanding the relationship
between the academic grade level for the child and the total costs spent per child per
academic year. They performed a multiple regression analysis using total cost as the
dependent variable and academic year (x1) as the independent variables. The multiple
regression analysis produced the following tables.
Using a = 0.05 to test the null hypothesis H0: b1 = 0, the critical t value is ____.
a) 1.311
b) 1.699
c) 1.703
d) 2.502
e) 2.052
A nonzero value of the skewness indicates asymmetry of the distribution of the data.
Catherine Chao, Director of Marketing Research, is evaluating consumer acceptance of
a new toothpaste package. She randomly selects a sample of 200 households. Forty
households prefer the new package to all other package designs. The point estimate for
this population proportion is _______.
a) 0.20
b) 0.25
c) 0.40
d) 0.45
e) 0.55
Correlation coefficients may be computed for parametric and nonparametric data. If the
data are interval data, which of the following should be used?
a) Pearson correlation coefficient
b) Spearman correlation coefficient
c) Gaussian correlation coefficient
d) De Moivre correlation coefficient
e) Gossett correlation coefficient
A Mann-Whitney U test was performed to determine if there were differences in the
average compute time for Dallas residents versus Atlanta residents. The travel time for
22 commuters in Dallas was compared to the travel time for 28 commuters in Atlanta.
The Ustatistic was calculated to be 58.0 based on the sample sizes of 22 and 28. What
is the zvalue for this test?
a) 51.17
b) 308
c) 0.117
d) -4.88
e) -2.44
Suppose 5% of the population have a certain disease. A laboratory blood test gives a
positive reading for 95% of people who have the disease. What is the probability of
testing positive and having the disease?
a) 0.0475
b) 0.95
c) 0.05
d) 0.9
e)0.02
Brian Vanecek, VP of Operations at Portland Trust Bank, is evaluating the service level
provided to walk-in customers. Brian would like to minimize the variance of waiting
time for these customers, since this would mean each customer received the same level
of service. Accordingly, his staff recorded the waiting times for 15 randomly selected
walk-in customers, and determined that their mean waiting time was 15 minutes and
that the standard deviation was 4 minutes. Assume that waiting time is normally
distributed. The 90% confidence interval for the population variance of waiting times is
________.
a) 9.46 to 34.09
b) 56.25 to 64.87
c) 11.05 to 16.03
d) 8.58 to 39.79
e) 12.50 to 42.35