How Jim Simons revolutionised investing

Great investors are often known by a signature style. Warren Buffett made it big by investing in companies he thought cheap and holding on for many years. George Soros bet on macroeconomic events, at one point almost breaking the Bank of England. Jim Simons, who died on May 10th at the age of 86, was more mysterious. He plumbed the quantitative depths in often unexplainable ways.

He may also have been the best of the lot. “There is one GOAT [greatest of all time]. His name was Jim Simons,” as Clifford Asness, co-founder of AQR, a hedge fund, put it to the Wall Street Journal. The flagship Medallion fund of Renaissance Technologies, Mr Simons’s firm, generated a whopping $100bn in trading profits over the three decades to 2018. Its 66% average annual return was even more astounding. No other big fund came close.