答案和详解如下： 6、A distribution that has positive excess kurtosis: A) is more peaked than a normal distribution. B) is less peaked than a normal distribution. C) has thinner tails than a normal distribution. D) is more skewed than a normal distribution. The correct answer was A) A distribution with positive excess kurtosis is one that is more peaked than a normal distribution. 7、A distribution that is more peaked than normal is: A) skewed. B) platykurtic. C) leptokurtic. D) geometric. The correct answer was C) A distribution that is more peaked than normal is leptokurtic. A distribution that is flatter than normal is platykurtic. 8、Which of the following statements concerning a distribution with positive skewness and positive excess kurtosis is FALSE? A) The mean will be greater than the mode. B) It has a lower percentage of small deviations from the mean than a normal distribution. C) There are a large number of positive outliers. D) It has fatter tails than a normal distribution. The correct answer was B) A distribution with positive excess kurtosis has a higher percentage of small deviations from the mean than normal. So it is more “peaked” than a normal distribution. A distribution with positive skew has a mean > mode.
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发表于 2008-4-8 18:27
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