Suppose a researcher is testing a null hypothesis that
= 61. A random sample of n= 36
is taken resulting in a sample mean of 63 and s = 9. The observed tvalue is _______.
a) -0.22
b) 0.22
c) 1.33
d) 8.08
e) 7.58
A researcher wishes to determine the difference in two population means. To do this,
she randomly samples 9 items from each population and computes a 90% confidence
interval. The sample from the first population produces a mean of 780 with a standard
deviation of 240. The sample from the second population produces a mean of 890 with
a standard deviation of 280. Assume that the values are normally distributed in each
population. The point estimate for the difference in the means of these two populations
is _______.
a) -110
b) 40
c) -40
d) 0
e) 240
Max Sandlin is exploring the characteristics of stock market investors. He found that
sixty percent of all investors have a net worth exceeding $1,000,000; 20% of all
investors use an online brokerage; and 10% of all investors a have net worth exceeding
$1,000,000 and use an online brokerage. An investor is selected randomly, and E is the
event “net worth exceeds $1,000,000” and O is the event “uses an online brokerage.”
P(O E) = _____________.
a) 0.17
b) 0.50
c) 0.80
d) 0.70
e) 0.10
Abby Kratz, a market specialist at the market research firm of Saez, Sikes, and Spitz, is
analyzing household budget data collected by her firm. Abby’s dependent variable is
weekly household expenditures on groceries (in $’s), and her independent variables are
annual household income (in $1,000’s) and household neighborhood (0 = suburban, 1 =
rural). Regression analysis of the data yielded the following table.
For a rural household with $90,000 annual income, Abby’s model predicts weekly
grocery expenditure of ________________.
a) $156.19
b) $224.98
c) $444.62
d) $141.36
e) $175.86
Ophelia O’Brien, VP of Consumer Credit of American First Banks (AFB), is designing
a p chart to monitor the default rate on personal loans at the AFB member banks. Her
data includes the proportion in default for 30 samples of personal loans. Each sample
contains 50 loans, and the average of the 30 proportions is 0.05. The lower control limit
for Ophelia’s p chart is _____________.
a) 0.0000
b) 0.0204
c) 0.0308
d) 0.0149
e) -1.0000
A commuter travels many miles to work each morning. She has timed this trip 5 times
during the last month. The time (in minutes) required to make this trip was 34, 39, 41,
35, and 41. The mode time required for this trip was _______.
a) 39
b) 41
c) 37.5
d) 38
e) 35
Ray Crofford is evaluating investment alternatives to invest $100,000 which he
inherited from his grandfather. His investment advisor has identified four alternatives
and constructed the following payoff table which shows expected profits (in $10,000’s)
for various market conditions.
For the combination of ‘T-Bills’ and ‘Neutral’, the opportunity loss is _________.
a) 0
b) 5
c) 7
d) 8
e) -10
A manager wants to predict the cost (y) of travel for salespeople based on the number of
days (x) spent on each sales trip. The following model has been developed: y = $400 +
120x. If a trip took 3 days, the predicted cost of the trip is _____________.
a) 760
b) 360
c) 523
d) 1560
e) 1080
A market research firms conducts studies regarding the success of new products. The
company is not always perfect in predicting the success. Suppose that there is a 50%
chance that any new product would be successful (and a 50% chance that it would fail).
In the past, for all new products that ultimately were successful, 80% were predicted to
be successful (and the other 20% were inaccurately predicted to be failures). Also, for
all new products that were ultimately failures, 70% were predicted to be failures (and
the other 30% were inaccurately predicted to be successes). For any randomly selected
new product, what is the probability that the market research firm would predict that it
would be a success?
a) 0.80
b) 0.50
c) 0.45
d) 0.55
e) 0.95
In estimating the sample size necessary to estimate p, if there is no good approximation
for the value of p available, the value of ____ should be used as an estimate of p in the
formula.
a) 0.10
b) 0.50
c) 0.40
d) 1.96
e) 2.00
The following scatter plot indicates that _________.
a) a log x transform may be useful
b) a log y transform may be useful
c) a x2transform may be useful
d) no transform is needed
e) a 1/x transform may be useful
A cost accountant is developing a regression model to predict the total cost of
producing a batch of printed circuit boards as a linear function of batch size (the
number of boards produced in one lot or batch). The intercept of this model is the
______.
a) batch size
b) unit variable cost
c) fixed cost
d) total cost
e) total variable cost
If x, the time (in minutes) to complete an change job at certain auto service station, is
uniformly distributed over the interval 20 to 30, inclusively (20 x 30), then the
probability that an oil change job will be completed 24 minutes or more, i.e., P(x 24) is
__________________.
a) 0.100
b) 0.000
c) 0.333
d) 0.600
e) 1.000
A time series analysis was performed to determine the number of new online customers
that joined the “Jelly of the Month Club”. The actual number of new customers, the
forecast values and error terms is presented in the following table. The mean absolute
deviation (MAD) for this forecast is ___________.
a) -0.50
b) 0.50
c) 1.50
d) 7.00
e) 3.00
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) x1 is the only predictor variable significant at the 5% level
d) x2 is the only predictor variable significant at the 5% level
e) the intercept is not significant at the 5% level
A perfect Spearman correlation of +1 or −1 between two variables indicates
a) a perfect linear relationship between the two variables
b) a perfect monotone function of the two variables.
c) the Pearson correlation is 1
d) the Pearson correlation is +1 or -1
e) the two variables are not related.
In decision-making under uncertainty, an optimistic approach is the __________.
a) maximin criterion
b) maximax criterion
c) Hurwicz criterion
d) minimax regret strategy
e) maximin regret strategy
Sue Taylor, Director of Global Industrial Sales, is concerned by a deteriorating sales
trend.
Specifically, the number of customers is stable at 1,500, but they are purchasing less
each year.
She orders her staff to search for causes of the downward trend by surveying all 1,500
industrial customers. Sue is ordering a __________.
a) statistic from the industrial customers
b) census of the industrial customers
c) sample of the industrial customers
d) sorting of the industrial customers
e) parameter of the industrial customers
According to the following graphic, X and Y have _________.
a) strong negative correlation
b) virtually no correlation
c) strong positive
correlation
d) moderate
negative correlation
e) weak negative
correlation
Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities in
the payroll system. She knows that 2,500 payroll vouchers have been issued since
January 1, 2000, and her staff doesn’t have time to inspect each voucher. So, she
randomly selects 53 as a starting point and orders her staff to inspect the 53rd voucher
and each voucher at an increment of 100 (53, 153, 253, etc.). Her sample is a
___________.
a) stratified sample
b) simple random sample
c) convenience sample
d) cluster sample
e) systematic sample
The number of cars arriving at a toll booth in five-minute intervals is Poisson
distributed with a mean of 3 cars arriving in five-minute time intervals. The probability
of 3 cars arriving over a five-minute interval is _______.
a) 0.2700
b) 0.0498
c) 0.2240
d) 0.0001
e) 0.0020
For a certain data set the regression equation is y = 37 + 13x. The correlation coefficient
between y and x in this data set _______.
a) must be 0
b) is negative
c) must be 1
d) is positive
e) must be 3
A new sales person is paid a commission on each sale. This person made $2,000 his
first month on the job. From this he concludes that he will make $24,000 during his first
year. This is an example of _______.
a) inferential statistics
b) nominal data
c) descriptive statistics
d) deferential statistics
e) nonparametric statistics
While reviewing staffing plans for a new pilot plant, Colin Chenaux, VP of Operations
at Clovis Chemicals, Inc., designed an experiment to test the effects of “supervisor’s
style” and “training method” on the productivity of operators. The treatment levels
were: (1) authoritarian, and participatory for supervisor’s style, and (2) technical
manuals, training films, and multimedia for training method. Three qualified applicants
were randomly selected and assigned to each of the six cells. Colin’s null hypothesis for
training methods is _____________.
a)
b)
1
2
3
c)
1
2
3
d)
1
2
3
e)
1
2≥
3
Assigning probability 1/52 on drawing the ace of spade in a deck of cards is an example
of assigning probabilities using the ________________ method
a) subjective probability
b) relative frequency
c) classical probability
d) a priori probability
e) a posterior probability
Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the
service level provided to walk-in customers. Accordingly, he plans a sample of waiting
times for walk-in customers. If the population of waiting times has a mean of 15
minutes and a standard deviation of 4 minutes, the probability that Albert’s sample of 64
will have a mean less than 16 minutes is ________.
a) 0.4772
b) 0.0228
c) 0.9072
d) 0.9544
e) 0.9772
The Kruskal-Wallis test is to be used to determine whether there is a significant
difference in the satisfaction rating (alpha = 0.05) between three brands of boxed cake
mix. Shoppers were asked to rate their satisfaction on various attributes and an
aggregate satisfaction score ranging from 1-50 was computed. The following data were
obtained:
For this test, how many degrees of freedom should be used?
a) 3
b) 2
c) 4
d) 8
e) 1
An “all possible regressions” search of a data set containing 5 independent variables
will produce ______ regressions.
a) 31
b) 10
c) 25
d) 32
e) 24
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) The class widths are too large.
d) The second and the third interval overlap.
e) There are too few intervals.
David Desreumaux, VP of Human Resources of American First Banks (AFB), is
reviewing the employee training programs of AFB banks. Based on a recent census of
personnel, David knows that the variance of teller training time in the Southeast region
is 8, and he wonders if the variance in the Southwest region is the same number. His
staff randomly selected personnel files for 15 tellers in the Southwest Region, and
determined that their mean training time was 25 hours and that the standard deviation
was 4 hours. Assume that teller training time is normally distributed. Using = 0.10, the
critical values of chi-square are ________.
a) 7.96 and 26.30
b) 6.57 and 23.68
c) -1.96 and 1.96
d) -1.645 and 1.645
e) -6.57 and 23.68
For an exponential distribution with a lambda (l) equal to 20, the mean equal to
_______.
a) 20
b) .05
c) 4.474
d) 1
e) 2.11
Anita Cruz recently assumed responsibility for a large investment portfolio. She
wonders whether industry sector influences investment objective. Her staff prepared the
following contingency table from a random sample of 200 common stocks.
Anita’s null hypothesis is ______________.
a) “investment objective” is related to “industry sector”
b) “investment objective” influences “industry sector”
c) “investment objective” is not independent of “industry sector”
d) “investment objective” is independent of “industry sector”
e) “growth” and “income” are independent