Early In 2012, a portfolio in JPMorgan Chase’s Chief Investment Office was running over its risk limits. Then a new value-at-risk model arrived, and the problem seemed to vanish. The new model roughly halved the portfolio’s reported risk. Months afterward, the trades that came to be called the “London Whale” https://aitradingsystemdevelopmen51739.wikififfi.com/2719136/when_the_risk_model_is_the_risk_institutional_lessons_in_algorithmic_trading_risk_management