James Harris Simons was an American hedge fund manager, mathematician, and philanthropist. He was the founder of Renaissance Technologies, a quantitative hedge fund based in East Setauket, New York. He and his fund are known to be quantitative investors, using mathematical models and algorithms to make investment gains from market inefficiencies. Due to the long-term aggregate investment returns of Renaissance and its Medallion Fund, Simons was described as the "greatest investor on Wall Street," and more specifically "the most successful hedge fund manager of all time".