Standard deviation measures how far numbers in a data set are spread out from an average value. In investing, it is used as a measurement of portfolio volatility.

Six Sigma is a data-driven approach to quality, aimed at reducing variation and the associated defects, wastes, and risks in any process. This article explores the basics of Six Sigma process quality ...

To interpret standard deviation as it pertains to volatility, you must understand the assumptions of a normal bell curve. When data is normally distributed, 68% of the values fall within one ...

Both the standard deviation and the covariance are important for understanding risk, especially when it comes to investing in a portfolio of different securities. To understand this better ...