摘要：The purpose of this research report is to evaluate the pricing performance of market advisory services for the 1995-2000 corn and soybean crops. Certain explicit assumptions are made to produce a consistent and comparable set of results across the different advisory programs. These assumptions are intended to accurately depict "real-world" marketing conditions. Several key assumptions are: i) with a few exceptions, the marketing window for a crop year runs from September before harvest through August after harvest, ii) cash prices and yields refer to a central Illinois farm, iii) storage is assumed to occur at on-farm or commercial sites, and iv) marketing loan recommendations made by advisory programs are followed wherever feasible. Based on these assumptions, the net price received by a subscriber to market advisory programs is calculated for the 1995-2000 corn and soybean crops. Market and farmer benchmarks are developed for the performance evaluations. Two market benchmarks are specified in order to test the fragility of performance results to changing benchmark assumptions. The 24-month market benchmark averages market prices for the entire 24-month marketing window. The 20-month market benchmark is computed in a similar fashion, except the first four months of the marketing window are omitted. The farmer benchmark is based upon the USDA average price received series for corn and soybeans in Illinois. The same assumptions applied to advisory program track records are used when computing the market and farmer benchmarks. Four basic indicators of performance are applied to advisory program prices and revenues over 1995-2000. The results provide limited evidence that advisory programs as a group outperform market benchmarks, particularly after considering risk. In contrast, substantial evidence exists that advisory programs as a group outperform the farmer benchmarks, even after taking risk into account. Whether the superior performance of advisory programs versus the farmer benchmark is attributed to luck or skill depends on one's theoretical perspective. Efficient market theory favors a luck interpretation, while behavioral market theory favors a skill interpretation. Regardless of the theoretical perspective, there is little evidence that advisory programs with superior performance can be usefully selected based on past performance.
