The Coefficient of Variation (CV) of the mean, a measurement of
variability of the mean price, is calculated as the standard error divided by
the mean. As a measure of precision reflecting the error due to sampling, it can
also be used to construct a confidence interval for the population mean. For
example, a mean price of $1.67 and a CV of 0.004 (.4%) indicates at the 95%
confidence level that the population mean price has an upper limit of $1.68
($1.67 + 1.96*0.004*$1.67) and a lower limit of $1.66 ($1.67 -
1.96*0.004*$1.67). |