When reviewing cash flow data for your small business, knowing the standard deviation can help you determine if the numbers are out of whack. Calculating standard deviation manually can be ...

WHEN a series of numbers can legitimately be regarded as random samples from a normal distribution, the mean range within small sub-groups, multiplied by a factor depending only on group-size, gives a ...

In response to my article, Is the Stock Market Too Concentrated?, which relied upon standard-deviation calculations to assess investment risk, a reader wrote: “My problem [with your argument] is ...