The college of business was interested in comparing the interaction of academic status
and class time on class attendance. Three different classes were sampled for each cell in
the table. The means for each cell follow.
What are the error degrees of freedom?
A. 44
B. 14
C. 30
D. 2
The production department has installed a new spray machine to paint automobile
doors. As is common with most spray guns, unsightly blemishes often appear because
of improper mixture or other problems. A worker counted the number of blemishes on
each door. Most doors had no blemishes; a few had one; a very few had two; and so on.
The average number was 0.5 per door. The distribution of blemishes followed the
Poisson distribution. Out of 10,000 doors painted, about how many would have no
blemishes?
A. About 6,065
B. About 3,935
C. About 5,000
D. About 500
The college of business was interested in comparing the interaction of academic status
and class time on class attendance. Three different classes were sampled for each cell in
the table. The means for each cell follow.
What are the interaction degrees of freedom?
A. 10
B. 2
C. 4
D. 8
Two samples, one of size 14 and the second of size 13, are selected to test the difference
between two population means. How many degrees of freedom are used to find the
critical value? Assume the population standard deviations are equal.
A. 27
B. 26
C. 25
D. 14
What does the correlation matrix for a multiple regression analysis contain?
A. Multiple correlation coefficients
B. Simple correlation coefficients
C. Multiple coefficients of determination
D. Multiple standard errors of estimate
The performance of personal and business investments is measured as a percentage,
“return on investment.” What type of variable is “return on investment”?
A. Qualitative
B. Continuous
C. Attribute
D. Discrete
The sum of the deviations of each data value from this measure of central location will
always be zero.
A. Mode
B. Mean
C. Median
D. Standard deviation
Besides measuring change in the prices of goods and services, the consumer price index
has a number of other applications such as:
A. to determine real disposable personal income.
B. to deflate sales or other data series.
C. to find the purchasing power of the dollar.
D. all of these
The size of the sampling error is ________.
A. directly related to the sample size’”in other words, the larger the sample size, the
larger the sampling error
B. directly related to the population mean’”in other words, the larger the mean, the
larger the sampling error
C. inversely related to the sample size’”in other words, the larger the sample size, the
smaller the sampling error
D. inversely related to the population standard deviation’”in other words, the smaller the
standard deviation, the larger the sampling error
What distribution does the F distribution approach as the sample size increases?
A. Binomial
B. Normal
C. Poisson
D. Exponential
Which statement(s) is/are correct about the t distribution?
A. The mean is zero.
B. Its shape is symmetric.
C. Its dispersion is based on degrees of freedom.
D. All apply.
The time to fly between New York City and Chicago is uniformly distributed with a
minimum of 120 minutes and a maximum of 150 minutes. What is the probability that a
flight is more than 140 minutes?
A. 1.00
B. 0.5
C. 0.333
D. 0.00
The technique that tallies types of defects and their frequency is called:
A. range charts.
B. Pareto analysis.
C. control charts.
D. fishbone diagram.
The sample variance of hourly wages was 10. What is the sample standard deviation?
A. $1.96
B. $4.67
C. $3.16
D. $10.00
What does the multiple standard error of estimate measure?
A. The change in for a change in X1
B. The variability of the residuals
C. The regression mean square error in the ANOVA table
D. The amount of explained variation
A consumer products company wants to increase the absorption capacity of a sponge.
Based on past data, the average sponge could absorb 3.5 ounces. After the redesign, the
absorption amounts of a sample of sponges were (in ounces): 4.1, 3.7, 3.3, 3.5, 3.8, 3.9,
3.6, 3.8, 4.0, and 3.9. At the 0.01 level of significance, what is the decision rule to test if
the new design increased the absorption of the sponge?
A. Reject the null hypothesis if computed t is less than 2.580.
B. Reject the null hypothesis if computed t is greater than 2.821.
C. Reject the null hypothesis if computed z is 1.96 or larger.
D. Reject the null hypothesis if computed t is less than 2.764.
The National Center for Health Statistics reported that of every 883 deaths in recent
years, 24 resulted from an automobile accident, 182 from cancer, and 333 from heart
disease. What is the probability that a particular death is due to an automobile accident?
A. 24/883 or 0.027
B. 539/883 or 0.610
C. 24/333 or 0.072
D. 182/883 or 0.206
To calculate quarterly typical seasonal indexes, how many periods are included in the
ratio-to-moving-average method?
A. 2
B. 4
C. 6
D. 12
Fifty-five voters from a sample of 80 indicated that they favored casino gambling in
their city. The city council is interested in finding out whether or not there is a
significant difference between the proportions of those favoring and not favoring casino
gambling in their community.
The test statistic is ______.
A. 0.50
B. 3.71
C. 80
D. 3.24
A new car was put into production. It involved many assembly tasks. Each car was
inspected at the end of the assembly line and the number of defects per unit was
recorded. For the first 100 cars produced, there were 40 defective cars. Some of the cars
had no defects, a few had one defect, and so on. The distribution of defects followed a
Poisson distribution. Based on the first 100 cars produced, about how many out of
every 1,000 cars assembled should have one or more defects?
A. About 660
B. About 165
C. About 630
D. About 330
There are eight flights from Minneapolis to St. Cloud each day. The probability that any
one flight is late is 0.10. Using the binomial probability formula, what is the probability
that exactly 1 flight is late?
A consultant is planning a survey of corporate executives to determine their mean
amount of weekly work time. A pilot survey indicated that the mean work time per
week is 50 hours, with a standard deviation of 10 hours. The consultant wants to
estimate the mean weekly work time within five hours. The 95% level of confidence is
to be used. How many executives should be surveyed?
The pooled estimate of the proportion is found by dividing the total number of
successes by ___________________________.
If there is perfect correlation, the value of the correlation coefficient is __________.
A table showing the number of observations that have been grouped into each of several
classes is called a frequency ________________.