What can we conclude if the global test of regression rejects the null hypothesis?
A. Strong correlations exist among the variables.
B. No relationship exists between the dependent variable and any of the independent
variables.
C. At least one of the net regression coefficients is not equal to zero.
D. Good predictions are not possible.
The time series component that exhibits fluctuations over more than a year in time
above and below the secular trend is ________.
A. irregular
B. cyclical
C. seasonal
D. a trend
In a market test of a new chocolate raspberry coffee, a poll of 400 people (sample 1)
from Dobbs Ferry showed 250 preferred the new coffee. In Irvington, 170 out of 350
people (sample 2) preferred the new coffee. To test the hypothesis that a higher
proportion of people in Dobbs Ferry prefer the new coffee, what is the alternate
hypothesis?
A. H1: π1 < π2
B. H1: π1 > π2
C. H1: π1 = π2
D. H1: π1 ≠π2
An automatic machine inserts mixed vegetables into a plastic bag. Past experience
revealed that some packages were underweight and some were overweight, but most of
them had satisfactory weight.
What is the probability of selecting three packages that are satisfactory?
A. 0.900
B. 0.810
C. 0.729
D. 0.075
A personnel manager is concerned about absenteeism. She decides to sample employee
records to determine if absenteeism is distributed evenly throughout the six-day
workweek. The null hypothesis is: Absenteeism is distributed evenly throughout the
week. The 0.01 level is to be used. The sample results are:
What kind of frequencies are the numbers 12, 9, 11, 10, 9, and 9 called?
A. Acceptance frequencies
B. Critical frequencies
C. Expected frequencies
D. Observed frequencies
The computed chi-square value is positive because the difference between the observed
and expected frequencies is _____________.
A. Squared
B. Linear
C. Uniform
D. Always positive
What type of variable is “pounds of popcorn” served at a movie theater?
A. Interval
B. Ratio
C. Discrete
D. Continuous
To calculate monthly typical seasonal indexes, the specific seasonal indexes must be
averaged for:
A. every month.
B. every year.
C. every quarter.
D. every day.
It is claimed that in a bushel of peaches, less than 10% are defective. A sample of 400
peaches is examined and 50 are found to be defective. What is the critical value for α =
0.025?
A. +1.960
B. 1.645
C. -1.960
D. -1.645
Consider a continuous random variable x, which is uniformly distributed between 65
and 85. The probability of x taking on a value between 75 to 90 is ________.
A. 0.75
B. 1.00
C. 0.50
D. 0.075
The national sales manager for “I colored this” (ICT) T-shirts provides all salespersons
with the payoff table shown next, giving the estimated profit when a retailer purchases
from one to four dozen T-shirts. The probability of demand for each state of nature is
also shown.
How many dozen “I colored this” T-shirts should be purchased to yield the highest
payoff?
A. 1
B. 2
C. 3
D. 4
In the following table,
A. The median is 2.5.
B. The minimum value is 135.
C. The maximum value is 456.
D. The range is 33.
Using the following information:
If testing the hypothesis: H0: Ï = 0, the computed t-statistic is __________.
A. 9.49
B. 8.84
C. 8.18
D. Cannot be computed
A telemarketing firm is monitoring the performance of its employees based on the
number of sales per hour. One employee had the following sales for the last 20 hours.
Draw a dot plot for the data.
When computing the mean, the smallest value
A. can never be negative.
B. can never be zero.
C. can never be less than the mean.
D. can be any value.
Dice are used in a variety of games. A die is a six-sided cube with a number of dots on
each side. The number of dots ranges from one to six. If two die are used in a game,
how many outcomes are possible?
The following stem-and-leaf display reports the number of boats shipped per week by
Ottertail Boats, Inc.
11| 1 5 9
12| 0 1 2 2 6 9
13| 0 1 2 3 4 5 5 7 8 8 9
14| 2 6 8
15| 0 1 2 4 5 7 8 9
16| 1 5 7 9
How often did the company ship 111 boats in a week?
Chebyshev’s theorem is valid for any ________.
Suppose your annual 2001 salary was $40,000 and your 2006 salary was $52,000.
Assume the annual CPI rose from 177.1 to 202.9 during this period of time. What was
your real income in 2006?
The Nile Superstore is conducting a survey of consumer preferences for a new wireless
e-book reader. A sample of 160 people reveals that 120 would buy the new reader.
Estimate the value of the population proportion.
To construct a histogram, the class frequencies are plotted on the ________.
A population consists of 10 values. How many samples of size six are possible?
A manufacturer of golf club shafts inspects 50 shafts every day. Over the last ten days,
the number of defective shafts has been reported to be the following.
To construct a process control chart for the mean percent defective, what is the lower
control limit?
When computing a weighed mean, the denominator is always __________.