Question

In: Statistics and Probability

The ratio of the standard deviation to the mean of a random variable is called the...

The ratio of the standard deviation to the mean of a random variable is called the coefficient of variation. For each of the following distributions, decide whether increasing the mean of the random variable increases, decreases, or has no effect on the value of the coefficient of variation

a. Poisson with mean µ

b. exponential with mean µ

c. chi-square with n degrees of freedom

Solutions

Expert Solution

a. Poisson with mean µ

The value of mean increases the coefficient of variation is decreases

b. exponential with mean µ

There is no effect on coefficient of variation as increases value of mean

c. chi-square with n degrees of freedom

The value of mean increases the coefficient of variation is decreases


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