Systematic and Nonsystematic Risk in Farm Portfolio Selection
评估了系统性风险和非系统性风险作为农场规划模型中的风险度量，发现基于单指数模型的二次规划与全方差-协方差二次规划结果相似，而仅使用系统性风险的线性规划在多数收入水平下与全方差模型结果一致，表明单指数模型可作为实用替代方案。
Abstract The concepts of systematic and nonsystematic risk are evaluated as risk measures in farm planning models. A diagonal quadratic programming model based upon a single‐index model yields farm plans similar to the full variance‐covariance quadratic program with four of thirteen farm plans being identical. Surprisingly, a linear programming model using only systematic risk produces farm plans that are identical to the full variance‐covariance quadratic program for eleven of thirteen income levels. Accordingly, it is suggested that single‐index‐based programming models may prove to be practical alternatives for deriving mean‐variance‐efficient farm plans.