During the 1950s, I decided, as did many others, that many practical problems were beyond analytic solution and that simulation techniques were required. At RAND, I participated in the building of large logistics simulation models; at General Electric, I helped build models of manufacturing plants.

Portfolio theory, as used by most financial planners, recommends that you diversify with a balance of stocks and bonds and cash that's suitable to your risk tolerance.

Diversifying sufficiently among uncorrelated risks can reduce portfolio risk toward zero. But financial engineers should know that's not true of a portfolio of correlated risks.

Harry Markowitz Quotes