Marshall Hargrave is a stock analyst and writer with 10+ years of experience covering stocks and markets, as well as analyzing and valuing companies. Dr. JeFreda R. Brown is a financial consultant, ...

In this paper, we provide Poincaré-type upper and lower variance bounds for a function g(X) of a discrete integer-valued random variable (r.v.) X, in terms of the (forward) differences of g up to some ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Robert Kelly is managing director of XTS ...

Stock's historical variance measures its return stability over time. Higher variance indicates greater return unpredictability and risk. Calculate variance using Excel to simplify the process for ...