Ralph Vince’s Portfolio Management Formulas (Nov 1990) is not a book you finish; it is a book you compute . It forces you to stop looking at the market and start looking at your sequence of trades .
Before Vince, traders relied heavily on "Risk of Ruin" tables. These tables told you the probability of losing your entire account based on a fixed bet size. Vince pointed out a fatal flaw: These tables assume you bet a fixed number of contracts (e.g., 1 contract per trade), regardless of account size. Ralph Vince’s Portfolio Management Formulas (Nov 1990) is