longbridge-factor-research A systematic framework for testing whether a quantitative factor adds predictive value for future returns — covering IC analysis, information ratio, decile portfolio construction, and factor decay. Response language : match the user's input language — Simplified Chinese / Traditional Chinese / English. When to use - "帮我分析 PE 因子的 IC" , "test IC for the PE factor on A-shares" - "动量因子有效吗" , "is momentum factor effective on HK stocks" - "做个分层回测" , "run a decile portfolio backtest" - "这个因子多少期后失效" , "how many periods until this factor decays" - "IC 序列自相关怎么算" , "calculate…