美國農民產銷管道之互補性與替代性檢驗

Testing for Complementarities and Substitutabilities among Marketing Arrangements Used by U.S. Farmers

使用某一組織模式或實作如果能夠增加（減少）另一種組織模式的邊際報酬則兩種組織模式稱之為具有互補性（替代性）。本研究探討產銷通路間的相關性並控制農場與農民可觀察到與不可觀察到的異質性，以此檢驗美國農民所使用不同的產銷通路是否具有互補性或替代性的可能。本研究以模擬最大概似法 (simulated maximum likelihood method, SMLE) 估計具有無法觀察到之異質性的機率單元 (Probit) 模型。研究結果顯示不同的產銷通路間具有替代性，此結果在不同的農產品與不同的計量模型設定下都具有相當一致的結果。

Two organizational modes or practices are said to be complements(substitutes) if the implementation of one practice increases (decreases)the marginal return of using the other practice. In this study, we test forthe implication of complementarities and substitutabilities among variousmarketing arrangements used by U.S. farmers by examining thecorrelation among marketing arrangements (practices) conditional onfarm/farmer observed and unobserved heterogeneities. The Probit modelwith unobserved heterogeneity is estimated using the simulatedmaximum likelihood method (SMLE). In our results, we foundsubstitutabilities among different marketing arrangements. The resultsare robust across different commodities and across different econometricspecifications.