1) If you are interested in comparing
variation in sales for small and large stores selling similar goods, which of
the following is the most appropriate measure of dispersion?
A) the range
B) the interquartile range
C) the standard deviation
D) the coefficient of variation
2) Suppose you are told that the mean of a
sample is below the median. What does this information suggest about the
distribution?
A) The distribution is symmetric.
B) The distribution is skewed to the right
or positively skewed.
C) The distribution is skewed to the left
or negatively skewed.
D) There is insufficient information to
determine the shape of the distribution.
3) For the following scatter plot, what
would be your best estimate of the correlation coefficient?
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A) -0.8
B) -1.0
C) 0.0
D) -0.3
4) Given a set of 25 observations, for
what value of the correlation coefficient would we be able to say that there is
evidence that a relationship exists between the two variables?
A).jpg”> ? 0.40
B).jpg”> ? 0.35
C).jpg”> ? 0.30
D).jpg”> ? 0.25
5) Which of the following statements is
true about the correlation coefficient and covariance?
A) The covariance is the preferred measure
of the relationship between two variables since it is generally larger than the
correlation coefficient.
B) The correlation coefficient is a
preferred measure of the relationship between two variables since its
calculation is easier than the covariance.
C) The covariance is a standardized
measure of the linear relationship between two variables.
D) The covariance and corresponding
correlation coefficient are represented by different signs, one is negative
while the other is positive and vice versa.
6) For the following scatter plot, what
would be your best estimate of the correlation coefficient?
.jpg”>
A) 1.0
B) 0.7
C) 0.3
D) 0.1
7) Which of the following descriptive
statistics is least affected by outliers?
A) mean
B) median
C) range
D) standard deviation
8) Which of the following statements is
true?
A) The correlation coefficient is always
greater than the covariance.
B) The covariance is always greater than
the correlation coefficient.
C) The covariance may be equal to the
correlation coefficient.
D) Neither the covariance nor the
correlation coefficient can be equal to zero.
9) Which measures of central location are
not affected by extremely small or extremely large data values?
A) arithmetic mean and median
B) median and mode
C) mode and arithmetic mean
D) geometric mean and arithmetic mean
10) Suppose you are told that sales this
year are 30% higher than they were six years ago. What has been the average
annual increase in sales over the past six years?
A) 5.0%
B) 4.5%
C) 4%
D) 3.5%
