1. Suppose we have the following data: 12, 17, 13, 25, 16, 21, 30,
14, 16, and 18. To find the 10% trimmed mean, what numbers
should be deleted from the calculation? - CORRECT
REPLY>>> -12 and 30
2. Which of the following is not resistant to the outliers in a data
set?
a. Median
b. Mean
c. Variance
d. Interquartile range - CORRECT REPLY>>> -b.
mean
3. The pth percentile is a value such that at least p percent of the
observations are: - CORRECT REPLY>>> -less than or
equal to this value.
4. Which of the following provides a measure of central location
for the data?
a. Mean
b. Variance
c. Mode
, d. Standard deviation - CORRECT REPLY>>> -a.
mean
5. When testing water for chemical impurities, results are often
reported as BDL, that is, below detection limit. The following
data set gives the measurements of the amount of lead in a
series of water samples taken from inner-city households
(ppm):
6. 5, 7, 12, BDL, 10, 8, BDL, 20, 6
7. Which of the following is correct?
a. The mean lead level in the water is about 10 ppm.
b. The median lead level in the water is 8 ppm.
c. The mean lead level in the water is about 8 ppm.
d. The median lead level in the water is 7 ppm. -
CORRECT REPLY>>> -d. The median lead level
in the water is 7 ppm.
8. A student made scores of 85, 56, and 91 on her first three
statistics tests. What score does she need to make on her next
test to have an 80 test average? - CORRECT
REPLY>>> -88
9. Growth factors for the population of Dallas in the past five years
have been 1, 2, 3, 4, and 5, respectively. The geometric mean is:
- CORRECT REPLY>>> -^5square root 120
, 10. A sample of 99 distances has a mean of 24 feet and a
median of 21.5 feet. Unfortunately, it has just been discovered
that an observation that was erroneously recorded as "30"
actually had a value of "35." If we make this correction to the
data, then: - CORRECT REPLY>>> -the median
remains the same, but the mean is increased.
11. A numerical value used as a summary measure for a
sample, such as sample mean, is known as a: - CORRECT
REPLY>>> -sample statistic.
12. The measure of location that is most likely to be
influenced by extreme values in a data set is the: -
CORRECT REPLY>>> -mean
13. A student was performing an experiment that compared a
new high protein food to the old food for pigs. He found the
mean weight gain for subjects consuming the new food to be
12.8 pounds with a standard deviation of 3.5 pounds. Later, he
realized that the scale was out of calibration by 1.5 pounds
(meaning that the scale weighed items 1.5 pounds more). What
should be the summary measures, mean and standard
deviation, for the subjects consuming the new food? -
CORRECT REPLY>>> -The mean should be 11.3 and
the standard deviation should remain unchanged.