James Harris "Jim" Simons (born 1938) is an American mathematician, hedge fund manager, and philanthropist. Considering his background as a code breaker and an expert in pattern recognition For more than twenty years, Simons' Renaissance Technologies hedge fund, which trades in markets around the world, has employed complex mathematical models to analyze and execute trades, many of them 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. Some also attribute Renaissance performance to employing Financial signal processing techniques such as pattern recognition.