[[Start here]] → [[Sources]] → Bill O’Shaugnessy --- [What Works on Wall Street](https://www.amazon.co.uk/What-Works-Wall-Street-Fourth/dp/0071625763/) was a pivotal book for me - as it inspired the formation of the Stockopedia StockRanks. In the 4th edition he designed some composite factors based on averaging the rankings of various ratios for every company in the market. He found that portfolios generated using composite ranks outperformed those composed across individual ratios (such as the P/E). See - [[value is best measured by a composite, not a single ratio]] ![[O’Shaugnessy - What Works on Wall Street.png]]