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Transcript
1) Which of the following measures of central location is affected most by extreme values?
A. Mean
B. Median
C. Mode
D. Geometric mean
2) Which level of measurement is required for the median?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
3) Which level of measurement is required for the mode?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
4) In a set of observations, which measure of central tendency reports the value that occurs most
often?
A. Mean
B. Median
C. Mode
D. Geometric mean
5) The weighted mean is a special case of what?
A. Mean
B. Median
C. Mode
D. Geometric mean
6) A sample of 5 companies were examined for changes in their relative market share. The results
showed the following increases and decreases: –5, 10, 10, 5, –10. Select the response which
represents the calculated mean of these results.
A. 8
B. 2
C. -2
D. 6
7) The difference between the sample mean and the population mean is called the
A. margin of error
B. population standard deviation
C. standard error of the mean
D. sampling error
8) A local trade union consists of plumbers and electricians classified according to rank:
Apprentice Journeyman Master Total
Plumbers 25 20 30 75
Electricians 15 40 20 75
40 60 50
A member of the union is selected at random. Given that the person selected is an electrician, what
is the probability that the person is a master?
A. .053
B. .133
C. .500
D. .267
9) Suppose a population consisted of 20 items. How many different samples of n = 3 are possible?
A. 6840
B. 1140
C. 20
D. 120
10) The mean and the variance are equal in
A. the normal distribution
B. the binomial distribution
C. the Poisson distribution
D. the hypergeometric distribution
11) In the 1936 Presidential Election Franklin D. Roosevelt defeated Alfred E. Landon in a landslide
vote. A Landon victory had been predicted by the Literary Digest, a magazine that ran the oldest,
largest, and most widely publicized of the polls at the time. The Digest's final prediction was based
on 10 million sample ballots mailed to prospective voters, and 2.3 million were returned. The sample
of voters was drawn from lists of automobile and telephone owners. Despite the massive size of this
sample, it failed to predict a Roosevelt victory, being off the mark by 19 percentage points. The
Literary Digest was wrong because
A. the sample size, although large, was not large enough
B. the right research questions were not asked
C. respondents intentionally lied about their preferred candidate
D. the sample used was not representative of the actual population at the time
12) In a study on the effect of reinforcement on learning from a company online training program,
two experimental treatments are planned: reinforcement given after every learning module, or
reinforcement given after every two learning modules. Reinforcement is accomplished with the
addition of more examples. Which one of the following control groups would serve best in this
study?
A. A group that does not read any of the learning modules.
B. A group that reads the modules using hardcopy only.
C. A group that reads the learning modules, but does not receive reinforcement.
D. A group that reads the learning modules with random reinforcement.
13) The central limit theorem is important to market researchers because it states that as sample
sizes increase, the distribution of the sample ________ collected from consumers on any topic of
interest being researched approaches the normal distribution.
A. medians
B. means
C. standard deviations
D. variances
QNT 561 Final Exam
14) To find confidence intervals for the mean of a normal distribution, the t distribution is usually
used in practical applications instead of the standard normal distribution because
A. the mean of the population is not known
B. the t distribution is more effective
C. the variance of the population is usually not known
D. the sample size is not known
15) We wish to develop a confidence interval for the population mean. The population follows the
normal distribution, the standard deviation of the population is 3, and we have a sample of 10
observations. We decide to use the 90% level of confidence. The appropriate value of to represent
the level of confidence is
A. z=1.65
B. z=1.96
C. z=1.833
D. z=1.812
16) Which of the following is a correct statement about a probability?
A. It may range from 0 to 1.
B. It may assume negative values.
C. It may be greater than 1.
D. It cannot be reported to more than 1 decimal place.
17) The special rule of addition is used to combine
A. independent events
B. mutually exclusive events
C. events that total more than one
D. events based on subjective probabilities
18) We use the general rule of multiplication to combine
A. events that are not independent
B. mutually exclusive events
C. events that total more than 1.00
D. events based on subjective probabilities
19) A discrete variable
A. is an example of a qualitative variable
B. can assume only whole number values
C. can assume only certain clearly separated values
D. cannot be negative
20) A nominal scale variable
A. usually involves ranking.
B. cannot assume negative values
C. has meaningful zero point
D. is usually based on counting
21) The ratio scale of measurement
A. usually the result of counting something
B. has meaningful zero point
C. may assume negative values
D. cannot have more than two categories
22) In the world of market research, the use of a questionnaire often plays a vital role in gaining
useful business intelligence because
A. it is a structured technique to collect secondary data
B. it represents a way to ask anything you want from respondents and receive valid information
C. it does not need to be tested
D. it can be used in conjunction with other techniques such as field interviews and focus
groups to maximize data input
23) A Type I error is
A. the correct decision
B. a value determined from the test statistic
C. rejecting the null hypothesis when it is true
D. accepting the null hypothesis when it is false
24) In a two-sample test of means for independent samples, we use the z distribution when
A. the population standard deviations are equal
B. both populations have at least 4,000 observations
C. both population standard deviations are known
D. nB and n(1-B) are both greater than 5
25) Which of the following is a requirement for a two-sample test of proportions?
A. The population standard deviations are equal.
B. Both populations are positively skewed.
C. Both samples are at least 30.
D. nB and n(1-B) are both greater than 5.
26) Bob is interested in opening a candy store in his town. He believes that his customers will spend
an average of $75 or more in annual purchases (the alternative hypothesis). Bob hires a consultant
to test this belief. The consultant tested this conjecture on a sample of 100 customers and found the
p-value for the test statistic satisfied p > .25, then
A. you would not reject the null hypothesis
B. you would reject the null hypothesis for alpha= .01
C. you would reject the null hypothesis for alpha= .05
D. you would reject the null hypothesis for alpha= .10
27) A carefully designed business experiment has just been concluded. Unfortunately, use of alpha
= .05 indicated no significant differences among four treatments. What useful information can you
supply future investigators when you report on this experiment?
A. The means are different but their variances are the same.
B. The estimated variance (and its df) can be useful to future investigators.
C. Pair-wise tests can be conducted to show significant differences.
D. Significant differences can be reported by changing the type I error rate from .05 to .10, .20, or
whatever is needed to declare significance.
28) A correlation matrix
A. shows all simple coefficients of correlation between variables
B. shows only correlations that are zero
C. shoes the correlations that are positive
D. shows only the correlations that are statistically significant
29) The multiple standard error of estimate is
A. the measure of variability to the prediction
B. negative when one of the net regression coefficients is zero
C. found by calculating SSR/SS total
D. the measure of accuracy of the prediction
30) A dummy variable or indicator variable
A. may assume only a value of 0 or 1
B. is another term for the dependent variable
C. is a quantitative variable
D. is a variable at a ratio or interval level of measurement