Measures of Dispersion

Which of the following is not a measure of dispersion?

• range

• variance

• standard deviation

• mode

Which of the measures of location is used in computing for the variance of a distribution?

• mean

• median

• mode

• midrange

It is defined as the square root of the variance.

• coefficient of variation

• midrange

• standard deviation

• kurtosis

If the dispersion is small, then the values in the distribution is close to the median.

• true

• false

Which of the measures of dispersion only uses two values in the distribution?

• range

• standard deviation

• variance

• mean deviation

The Empirical Rule says that 95% of the observations in a distribution will lie within plus and minus two standard deviations of the mean.

• true

• false

If two data sets have the same mean, then these sets also have the same standard deviations.

• true

• false

Which of the following is a characteristic of the range? Check all that apply.

• All values in the distribution are used in the calculation.

• It is influenced by extreme values.

• It is dependent on the mean.

• It is easy to compute and to understand.

Which of the following is a property of the standard deviation? Check all that apply.

• It can be negative.

• All the values in the distribution are used in computing for the standard deviation.

• It is in the same units as the original data

• It is the most widely reported measure of dispersion.

Chebyshev's Theorem states that regardless the shape of the distribution, at least

 $1-\frac{1}{k^2}$  of the observations will be within k standard deviations of the mean, where k is greater than 1.

• true

• false