台灣花卉拍賣的價值模式之實證分析：私有價值與共同價值

Abstract

台灣的批發花卉於民國77年開始採用電子化拍賣鐘的交易方式進行荷蘭式拍賣，在此之後即擁有大量的實證花卉拍賣資料可供利用。從學術觀點來說，則浮現許多拍賣理論的基本議題。例如，花卉的承銷人競價時是根據其本身的價值模式，如私有價值、共同價值等。在特定的拍賣市場與期間內，如何得知花卉承銷人的價值模式問題就自然浮現。於本論文中提出拍賣競爭指數作為求解價值模式問題的重要概念。接著建構花卉得標金額函數與拍賣競爭指標之間的關係。再使用最大概似法與非線性最小平方和法來分別估計不同價值模式下的競價參數。最後將兩種方法的參數估計結果利用郝思曼規格來進行檢定。假如在郝思曼檢定下，這些參數的估計結果是不一致的，則拒絕該價值模式。根據拍賣競爭指數，民國96年的台北花卉批發市場具有共同價值。相對地，民國91年的彰化花卉批發市場具有私有價值模式。

During 1988, wholesale flowers began to be traded through Dutch auction in Taiwan. Since then, a lot of empirical flower auction data became available. At the same time, many fundamental problems in auction theory arose from an academic research viewpoint. For example, flower buyers bid according to their value model such as private value, common value, etc. A natural question emerged is how to find the value model of the flower buyers for a given market at a specific period. In this thesis, Auction Competitiveness Index (ACI) has been developed as a key concept for finding the solution of the value model problem. Furthermore, each relationship between the winning bid price of flower and ACI for both value models is constructed. Then Maximum Likelihood Method (MLM) and Nonlinear Least Squares Method (NLSM) are applied to estimating the bidding parameters under the proposed value model, respectively. Next two sets of estimated parameters are analyzed through Hausman test. If the testing result shows inconsistent, then the proposed value model is rejected. With this ACI approach, it is found that Taipei flower wholesale market in 2007 owned a common value model. In contrast, the Changhua flower wholesale market in 2002 owned a private value model.