James Harris "Jim" Simons (born 1938) is an American hedge fund manager, mathematician, and philanthropist.
In 1982, Simons founded Renaissance Technologies, a private investment firm based in New York with over $15 billion under management; Simons is still at the helm, as CEO, of what is now one of the world's most successful hedge funds. Simons is estimated to be worth about $8.5 billion.
Simons lives with his wife in Manhattan and Long Island, and is the father of three.
Simons shuns the limelight and rarely gives interviews, citing Benjamin the Donkey in Animal Farm for explanation: "God gave me a tail to keep off the flies. But I'd rather have had no tail and no flies." On October 10, 2009, Simons announced he would retire on January 1, 2010 but remain at Renaissance as nonexecutive chairman.
For more than two decades, Simons' Renaissance Technologies' hedge funds, which trade in markets around the world, have employed mathematical models to analyze and execute trades, many automated. Renaissance uses computer-based models to predict price changes in easily-traded financial instruments. These models are based on analyzing as much data as can be gathered, then looking for non-random movements to make predictions.
Renaissance employs many specialists with non-financial backgrounds, including mathematicians, physicists and statisticians. The firm's latest fund is the Renaissance Institutional Equities Fund (RIEF). RIEF has historically trailed the firm's more well-known Medallion fund, a separate fund that only contains the personal money of the firm's executives.
"It's startling to see such a highly successful mathematician achieve success in another field," says Edward Witten, professor of physics at the Institute for Advanced Study in Princeton, NJ, and considered by many of his peers to be the most accomplished theoretical physicist alive... (Gregory Zuckerman, "Heard on the Street", Wall Street Journal, July 1, 2005).
In 2006 Simons was named Financial Engineer of the Year by the International Association of Financial Engineers. In 2007 he was estimated to have personally earned $2.8 billion, $1.7 billion in 2006, $1.5 billion in 2005, (the largest compensation among hedge fund managers that year) and $670 million in 2004.
Observers have been wondering how Renaissance's in-house Medallion Fund has managed to continue to outperform the stock market handily while funds open to outside investors have performed miserably. The violation could be related to the Nova Fund, a hedge fund that had very high returns which was mysteriously subsumed by the internal Medallion Fund.
(Source : http://en.wikipedia.org/ )