How can you describe the moving average method?
A. A method that smoothes out a time series.
B. A method to deseasonalize a time series.
C. A technique that results in a trend line equation.
D. A method for computing the slope of a trend line.
A two-tailed test of hypothesis was conducted and 60 values were above the median.
The computed z = 1.90. At the 0.05 level, what is the decision regarding the null
hypothesis?
A. Reject the null hypothesis with a 0.05 Type I error rate.
B. Fail to reject the null hypothesis.
C. Reject the null hypothesis with a 0.025 Type I error rate.
D. None of these.
Knowing the population standard deviation, a 95% confidence interval infers that the
population mean ___________.
A. is between 0 and 100%
B. is within 1.96 standard deviations of the sample mean
C. is within 1.96 standard errors of the sample mean
D. is too large
An insurance agent has appointments with four prospective clients tomorrow. From past
experience the agent knows that the probability of making a sale on any appointment is
1 out of 5. Using the rules of probability, what is the likelihood that the agent will sell a
policy to 3 of the 4 prospective clients?
A. 0.250
B. 0.500
C. 0.410
D. 0.026
Which word is NOT part of the definition of descriptive statistics?
A. Organizing
B. Analyzing
C. Presenting
D. Predicting
A maximax strategy will always choose the act or alternative that:
A. maximizes the expected monetary value.
B. minimizes the maximum regret or opportunity loss.
C. maximizes the potential payoff regardless of uncertainty.
D. guarantees a payoff for any state of nature.
A null hypothesis makes a claim about a __________.
A. Population parameter
B. Sample statistic
C. Sample mean
D. Type II error
When are two experimental outcomes mutually exclusive?
A. When they overlap on a Venn diagram.
B. If one outcome occurs, then the other cannot.
C. When the probability of one affects the probability of the other.
D. When the joint probability of the two outcomes is not equal to zero.
What is the range of values for a coefficient of correlation?
A. 0 to +1.0
B. -3 to +3 inclusive
C. -1.0 to +1.0 inclusive
D. Unlimited range
What must you know to develop a binomial probability distribution?
A. The probability of success
B. The probability of success and the number of trials
C. The probability of success and the number of successes
D. The number of trials and the number of successes
What is the critical value at the 0.05 level of significance for a goodness-of-fit test if
there are six categories?
A. 3.841
B. 5.991
C. 7.815
D. 11.070
Sponsors of a local charity decided to attract wealthy patrons to its $500-a-plate dinner
by allowing each patron to buy a set of 20 tickets for the gaming tables. The chance of
winning a prize for each of the 20 plays is 50-50. If you bought 20 tickets, what is the
chance of winning 15 or more prizes?
A. 0.250
B. 0.021
C. 0.006
D. 0.750
The members of each basketball team wear numbers on their jerseys. What scale of
measurement are these numbers considered?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
A hypothesis regarding the weight of newborn infants at a community hospital is that
the mean is 6.6 pounds. A sample of seven infants is randomly selected and their
weights at birth are recorded as 9.0, 7.3, 6.0, 8.8, 6.8, 8.4, and 6.6 pounds. The null
hypothesis is ______.
A. H0: = 6.6
B. H0: ≥ 6.6
C. H0: > 7.6
D. H0: ≤ 7.6
A recent study of the relationship between social activity and education for a sample of
corporate executives showed the following results.
The null hypothesis for the analysis is __________________________.
A. There is no relationship between social activity and education
B. The correlation between social activity and education is zero
C. As social activity increases, education increases
D. The mean of social activity equals the mean of education
An experiment involves selecting a random sample of 256 middle managers for study.
One item of interest is their annual income. The sample mean is computed to be
$35,420, and the sample standard deviation is $2,050. What is the sample standard error
of the mean?
A. $128.125
B. $138.36
C. $2,050
D. $8.01
What are the degrees of freedom for a contingency table analysis?
A. n – 1
B. Rows – Columns
C. (Rows) (Columns)
D. (Rows – 1) (Columns – 1)
The mean of a normal probability distribution is 500 and the standard deviation is 10.
About 95% of the observations lie between what two values?
A. 475 and 525
B. 480 and 520
C. 400 and 600
D. 350 and 650
A university surveyed recent graduates of the English Department for their starting
salaries. Four hundred graduates returned the survey. The average salary was $25,000,
with a standard deviation of $2,500. What is the best point estimate of the population
mean?
A. $25,000
B. $2,500
C. $400
D. $62.5
Quartiles divide a distribution into ___________.
A. 2 equal parts
B. 4 equal parts
C. 10 equal parts
D. 100 equal parts
The ___________ decision-making strategy maximizes the minimum gain.
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.
What is the standard error of the mean proportion of defective shafts?
To summarize the frequencies of two nominal or ordinal variables and compute
conditional probabilities, a ___________ can be used.
You have a decision to invest $10,000 in any of four different companies. You estimate
the probabilities that the economy will be favorable or unfavorable, and you estimate
the percent returns over the next year.
What company should you choose if the economy is favorable?
For the following probability distribution:
The mean is _____________.
The weekly sales from a sample of 10 computer stores yielded a mean of $25,900, a
median of $25,000, and a mode of $24,500. Given this, the shape of the distribution
would be _________.