The following class intervals for a frequency distribution were developed to provide
information regarding the starting salaries for students graduating from a particular
school:
Before data was collected, someone questioned the validity of this arrangement. Which
of the following represents a problem with this set of intervals?
a) There are too many intervals.
b) The class widths are too small.
c) Some numbers between 28,000 and 40,000 would fall into two different intervals.
d) The first and the second interval overlap.
e) There are too few intervals.
Elwin Osbourne, CIO at GFS, Inc., suspects that at least 25% of e-mail messages sent
by GFS employees are not business related. A random sample of 300 e-mail messages
was selected to test this hypothesis at the 0.01 level of significance. Fifty-four of the
messages were not business related. The null hypothesis is ____.
a)
= 30
b) n= 300
c) p< 0.25
d) p≠ 0.25
e) p= 0.25
Analysis of data for an autoregressive forecasting model produced the following tables.
The actual values of this time series, y, were 228, 54, and 191 for May, June, and July,
respectively. The predicted (forecast) value for August is __________.
a) -101.00
b) 104.54
c) 218.71
d) 21.56
e) -77.81
The social security number of employees would be an example of what level of data
measurement?
a) Interval level data
b) Ordinal level data
c) Nominal level data
d) Ratio level data
e) Relative level data
James Desreumaux, VP of Human Resources of American First Banks (AFB), is
reviewing the employee training programs of AFB banks. His staff randomly selected
personnel files for 10 tellers in the Southwest Region, and determined that their mean
training time was 25 hours and that the standard deviation was 5 hours. Assume that
training times are normally distributed. The 95% confidence interval for the population
variance of training times is ________.
a) 11.83 to 83.33
b) 2.37 to 16.67
c) 2.66 to 13.51
d) 13.30 to 67.57
e) 15.40 to 68.28
If a qualitative variable has 4 categories, how many dummy variables must be created
and used in the regression analysis?
a) 3
b) 4
c) 5
d) 6
e) 7
The probability of selecting 2 baseball players and 3 basketball players for an
intermural competition at a small sports camp would best be modeled with the
_______.
a) binomial distribution
b) hypergeometric distribution
c) Poisson distribution
d) hyperbinomial distribution
e) exponential distribution
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. If
= 0.05, the observed Fvalue is
___________.
a) 0.50
b) 2.00
c) 1.41
d) 0.91
e) 0.71
A researcher is estimating the average difference between two population means based
on matched”pairs samples. She gathers data on each pair in the study resulting in:
Assume that the data are normally distributed in the population. To obtain a 95%
confidence interval, the table tvalue would be _______.
a) 2.132
b) 1.86
c) 2.306
d) 2.976
e) 2.776
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 that
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
= .
01, the observed chi-square value is _______.
a) 1.18
b) 9.10
c) 21.75
d) 4.51
e) 2.73
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.
Analysis of Kevin’s data yielded the following ANOVA table.
Using
= 0.05, the appropriate decision is _____________.
a) inconclusive
b) reject the null hypothesis
1
2
3
c) reject the null hypothesis
1
2
3
d) do not reject the null hypothesis
1
2
3
e) do not reject the null hypothesis
1
2
3
Yvonne Yang, VP of Finance at Discrete Components, Inc. (DCI), wants a regression
model which predicts the average collection period on credit sales. Her data set includes
two qualitative variables: sales discount rates (0%, 2%, 4%, and 6%), and total assets of
credit customers (small, medium, and large). The number of dummy variables needed
for “sales discount rate” in Yvonne’s regression model is ________.
a) 1
b) 2
c) 3
d) 4
e) 7
A recent analysis of the number of rainy days per month found the following outcomes
and probabilities.
The mean of this distribution is _____________.
a) 2
b) 3
c) 4
d) 5
e) <1
Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities in
the payroll system. If 10% of the 5,000 payroll vouchers issued since January 1, 2000,
have irregularities, the probability that Pinky’s random sample of 200 vouchers will
have a sample proportion greater than .06 is ___________.
a) 0.4706
b) 0.9706
c) 0.0588
d) 0.9412
e) 0.9876
A market research firm is investigating the appeal of three package designs. The table
below gives information obtained through a sample of 200 consumers. The three
package designs are labeled A, B, and C. The consumers are classified according to age
and package design preference.
If one of these consumers is randomly selected and prefers design B, what is the
probability that the person is 25 or older?
a) 0.28
b) 0.14
c) 0.45
d) 0.27
e) 0.78
Which types of data are normally used in parametric statistics?
a) Interval or ratio level data
b) Ordinal or nominal level data
c) Nominal or ratio level data
d) Ratio or ordinal level data
e) Relative or ratio level data
A market research firm is investigating the appeal of three package designs. The table
below gives information obtained through a sample of 200 consumers. The three
package designs are labeled A, B, and C. The consumers are classified according to age
and package design preference.
Are “B” and “25 or older” independent and why or why not?
a) No, because P (25 or over | B) P (B)
b) Yes, because P (B) = P(C)
c) No, because P (25 or older | B) P (25 or older)
d) Yes, because P (25 or older B) 0
e) No, because age and package design are different things
According to the central limit theorem, for samples of size 169 drawn from a population
with µ = 1,014 and = 65, the mean of the sampling distribution of sample
means would equal _______.
a) 1,014
b) 65
c) 5
d) 6
e) 3
The staff of Mr. Wayne Wertz, VP of Operations at Portland Peoples Bank, prepared a
cumulative frequency ogive of waiting time for walk-in customers.
The percentage of walk-in customers waiting between 1 and 6 minutes was ___.
a) 22%
b) 11%
c) 37%
d) 10%
e) 67%
When forecasting with exponential smoothing, data from previous periods is
_________.
a) given equal importance
b) given exponentially increasing importance
c) ignored
d) given exponentially decreasing importance
e) linearly decreasing importance
Liz Chapa manages a portfolio of 250 common stocks. Her staff compiled the following
performance statistics for two new stocks.
The coefficient of variation for Salas Products, Inc. is __________.
a) 300%
b) 100%
c) 33%
d) 5%
e) 23%
Brian Vanecek, VP of Operations at Portland Trust Bank, is evaluating the service level
provided to walk-in customers. Accordingly, his staff recorded the waiting times for 64
randomly selected walk-in customers and determined that their mean waiting time was
15 minutes. Assume that the population standard deviation is 4 minutes. The 90%
confidence interval for the population mean of waiting times is ________.
a) 14.27 to 15.73
b) 14.18 to 15.82
c) 9.88 to 20.12
d) 13.86 to 16.14
e) 18.12 to 19.87
Cluster (or area) sampling is a type of random sampling technique.
An R Chart is to be developed for use in quality control. The average of the ranges is
calculated to be 0. 45. The sample sizes were 9 each. What would the lower control
limit be?
a) 0.8172
b) 0.6012
c) 0.0828
d) 0.1566
e) 0.7434
Financial analyst Larry Potts needs a sample of 100 securities listed on either the New
York Stock Exchange (NYSE) or the American Stock Exchange (AMEX). According to
the Wall Street Journal’s “Stock Market Data Bank,” 2,531 NYSE securities and AMEX
746 securities were traded on the previous business day. Larry directs his staff to
randomly select 77 NYSE and 23 AMEX securities. His sample is a ____________.
a) disproportionate systematic sample
b) disproportionate stratified sample
c) proportionate stratified sample
d) proportionate systematic sample
e) proportionate cluster sampling
Inspection of the following table of correlation coefficients for variables in a multiple
regression analysis reveals that the first independent variable entered by the forward
selection procedure will be ___________.
a) x2
b) x3
c) x4
d) x5
e) x1
The normal distribution is used to test about a population mean for large samples if the
population standard deviation is known. “Large” is usually defined as _______.
a) at least 10
b) at least 5% of the population size
c) at least 30
d) at least 12
e) at least 100
A research project was conducted to study the effect of smoking and weight upon
resting pulse rate. The response variable is coded as 1 when the pulse rate is low and 0
when it high. Smoking is also coding as 1 when smoking and 0 when not smoking.
Shown below is Minitab output from a logistic regression.
The log of the odds ratio or logit equation is:
a) log(S)=-1.19297+0.0250226 Weight-1.98717 Smokes
b) S=-1.98717+0.025226 Weight-1.19297 Smokes
c) Rating Pulse=-1.98717+0.025226 Weight-1.19297 Smokes
d) log(S) =-1.98717+0.025226 Weight-1.19297 Smokes
e) log(p)=-1.98717+0.025226 Weight-1.19297 Smokes
The following data is to be used to construct a regression model:
The value of the intercept is ________.
a) 16.49
b) 1.19
c) 1.43
d) 0.75
e) 1.30
A level of data measurement that has an absolute zero is called _______.
a) interval level
b) ordinal level
c) nominal level
d) ratio level
e) relative level
Data from a randomized block design are shown in the following table.
The Treatment Sum of Squares (SSB) is ________.
a) 4.67
b) 12
c) 2.33
d) 28.67
e) 11
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 experimental design is a ________.
a) factorial design
b) random block design
c) completely randomized design
d) normalized block design
e) incomplete block design
The weight of a USB flash drive is 30 grams and is normally distributed. Periodically,
quality control inspectors at Dallas Flash Drives randomly select a sample of 17 USB
flash drives. If the mean weight of the USB flash drives is too heavy or too light the
machinery is shut down for adjustment; otherwise, the production process continues.
The last sample showed a mean and standard deviation of 31.9 and 1.8 grams,
respectively. Using = 0.10, the critical “t” values are _______.
a) -2.120 and 2.120
b) -2.131 and 2.131
c) -1.753 and 1.753
d) -1.746 and 1.746
e) -2.567 and 2.567
Suppose the total time to fill a routine prescription at a local pharmacy is 35 minutes
based on the time the physician places the order to the time it is dispensed. Assume the
standard deviation is 11 minutes and the zscore is 0. What is x?
a) -35.0
b) 0.0
c) 70.0
d) 35.0
e) -1.0
Assume that a random variable has a Poisson distribution with a mean of 5 occurrences
per ten minutes. The number of occurrences per hour follows a Poisson distribution
with λ equal to _________
a) 5
b) 60
c) 30
d) 10
e) 20