Steven Nickolas is a writer and has 10+ years of experience working as a consultant to retail and institutional investors. Portfolio variance is a measure of the dispersion of returns of a portfolio.

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 ...

The standard deviation shows the extent of variation or spread of data. A larger standard deviation indicates that a data set has a wider spread around its mean. Process data usually has a normal ...