If the alternate hypothesis states that ≠4,000, where is the rejection region for the
hypothesis test?
A. In both tails
B. In the lower or left tail
C. In the upper or right tail
D. In the center
A two-way ANOVA with interaction has how many sources of variation?
A. 5
B. 4
C. 3
D. 2
In multiple regression, a dummy variable is significantly related to the dependent
variable when ______________.
A. The global test of the regression equation is rejected
B. The test of the dummy variable’s regression coefficient is rejected
C. The dummy variable is correlated with other independent variables
D. The dummy variable is coded as 2 or 3
In regression, the difference between the confidence interval and prediction interval
formulas is ________________.
A. the prediction interval is the square root of the confidence interval
B. the addition of “1” to the quantity under the radical sign
C. the prediction interval uses r2 and the confidence interval uses r
D. no difference.
Refer to the following breakdown of responses to a survey of “How confident are you
that you saved enough to retire?”
What is the class interval for the preceding frequency table?
A. 10
B. 20
C. 40
D. None Apply
A statistics professor receives an average of five e-mail messages per day from
students. Assume the number of messages approximates a Poisson distribution. What is
the probability that on a randomly selected day she will have two messages?
A. 0.0067
B. 0.0014
C. 0.4200
D. 0.0842
In a time series, high sales in the summer and low sales in the winter is called what?
A. Secular trend
B. Seasonal variation
C. Cyclical variation
D. Variation
When a confidence interval for a population mean is constructed from sample data,
__________.
A. we can conclude that the population mean is in the interval
B. we can conclude that the population mean is not in the interval
C. we can conclude, for an infinite number of samples and corresponding confidence
intervals, that the population mean is in a stated percentage of the intervals
D. we cannot make any inferences
Consider a standard normal random variable z. What is the value of z if the area to the
right of z is 0.2643?
A. 0.72
B. 0.28
C. 1.46
D. 0.63
Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches
41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that
they watch the late evening news on this local CBS station. What is the sample
proportion?
A. 0.41
B. 0.36%
C. 0.41%
D. 0.36
A store asks shoppers for their zip code to identify market areas. Zip codes are an
example of ratio data.
There are 2,000 eligible voters in a precinct. A total of 500 voters are randomly selected
and asked whether they plan to vote for the Democratic incumbent or the Republican
challenger. Of the 500 surveyed, 350 said they would vote for the Democratic
incumbent. Using the 0.99 confidence coefficient, what are the confidence limits for the
proportion that plan to vote for the Democratic incumbent?
A. 0.647 and 0.753
B. 0.612 and 0.712
C. 0.397 and 0.797
D. 0.826 and 0.926
The main purpose of descriptive statistics is to:
A. Summarize data in a useful and informative manner.
B. Make inferences about a population.
C. Determine if the data adequately represents the population.
D. Gather or collect data.
Refer to the following frequency distribution on days absent during a calendar year by
employees of a manufacturing company:
How many employees were absent for between 3 up to 6 days?
A. 31
B. 29
C. 14
D. 2
Two accounting professors decided to compare the variance of their grading procedures.
To accomplish this, they each graded the same 10 exams, with the following results:
What is the null hypothesis?
A.
B.
C.
D.
A soap manufacturer is experimenting with several formulas of soap powder. Three of
the formulas were selected for further testing by a panel of homemakers. The ratings for
the three formulas are as follows:
What is the sum of the ranks for Formula B?
To test the hypothesis that two population variances are equal, a random sample of size
13 was selected from the first population, and a random sample of size 21 was selected
from the second population. Given that the sample standard deviation from the first
population is larger than the sample standard deviation from the second population,
what is the F critical value using 0.01 as the significance level?
To compare the effect of weather on sales of soft drinks, a distributor surveyed people
in two regions of the country and asked if they purchased soft drinks in the last month.
The following are the results. The distributor would like to know if there is a difference
in sales between the two regions.
What is the proportion of sales made in Region B?
The arrival of customers at a service desk follows a Poisson distribution. If they arrive
at a rate of four every five minutes, what is the probability that more than four
customers arrive in a five-minute period?
The sign test is one of a few tests that can test the value of the __________.