The appraisal ratio is a financial measure of how much risk a fund manager takes based on the stocks it selectes. The appraisal ratio is comprised of two inputs the fund's alpha, which is the fund's risk-adjusted return and the portfolio's unsystematic risk. Unysystematic risk is a fancy way of saying how much risk is associated with non-market specific items. Fund managers attempt to hedge against this risk by picking a basket of stocks.
Below is the basic formula for the appraisal ratio:
Appraisal Ratio = Alpha/Unsystematic Risk
The higher the number the better the fund manager is at picking stocks. For example, let's say a fund manager's return for the year is 20% and the unsystematic risk is equal to 3%. The appraisal ratio for this fund manager would be 6.667.