摘要：In an update and extension of prior work this study found that the potato futures markets continued to provide very unreliable forecasts of subsequent spot prices. On the other hand and contrary to some past studies an extensive study here failed to turn up any convincing evidence of a cobweb pricing relationship. Moreover the increasing volatility of potato futures prices in the more recent time period raises questions regarding their value as hedging vehicles. Finally it is argued that the market's efficiency might be improved by expanding the current Maine potato contract to permit delivery of round white potatoes grown outside Maine.
