Appraisal Ratio

The Appraisal Ratio divides Jensen's alpha by the standard error of the alpha estimate (or equivalently, alpha by unsystematic risk). In insider-trading and quant scoring contexts, it serves as a refined measure of a signal's or trader's genuine forecasting ability, net of market beta exposure. Unlike raw alpha, which can be artificially inflated through leverage or concentrated factor bets, the Appraisal Ratio penalizes active bets that fail to justify their idiosyncratic risk. For quantitative platforms evaluating insider activity patterns or conviction-weighted signals, a high Appraisal Ratio indicates that observed abnormal returns arise from genuine information edge rather than systematic factor alignment.

In the context of insider-trading surveillance and quant score construction, the Appraisal Ratio is particularly valuable for discriminating signal quality. A trader or insider activity signal with high alpha but also high idiosyncratic volatility may generate a mediocre Appraisal Ratio, suggesting luck or factor timing rather than skill. Conversely, a consistent, low-volatility alpha stream yields a superior ratio and stronger conviction scoring weight. This metric helps hedge against overfitting to tail events and encourages robust, repeatable information edges in composite conviction indices and signal blending frameworks.