Which of the following statements regarding skewness is least accurate?
A) |
A distribution that is not symmetrical has skew not equal to zero. | |
B) |
In a skewed distribution, 95% of all values will lie within plus or minus two standard deviations of the mean. | |
C) |
A positively skewed distribution is characterized by many small losses and a few extreme gains. | |
For a normal distribution, the mean will be equal to its median and 95% of all observations will fall within plus or minus two standard deviations of the mean. For a skewed distribution, because it is not symmetrical, this may not be the case. Chebyshev’s inequality tells us that at least 75% of observations will lie within plus or minus two standard deviations from the mean.
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