台灣拖網漁業之效率評估——非意欲產出與擁擠投入的影響

Efficiency Evaluation of Trawl Fishery in Taiwan-The Impacts of Undesirable Outputs and Congestion Inputs

本研究採用資料包絡法（Data Envelopment Analysis）為效率評估模型，納入非意欲產出（非經濟漁獲）和擁擠投入（漁工超時工作）等問題，以Färe etal.（1989）所提出的拋物線距離函數為基礎，構建投入、產出不同比例型數學規劃模式，分析拖網漁業之效率。實證研究以「台灣底魚漁獲統計年報」所彙整之1976至1987年台灣單、雙船拖網漁船漁獲資料，探討各年度拖網漁船之平均效率，並以差額變數分別計算無效率漁船之潛在產能，以凸顯非意欲產出對漁船經營效率的影響。在本文實證結果發現，即便是台灣拖網漁船全盛時期（1976~1987年），每年平均仍存在著14%的改善空間，「潛在產能」達86,221公斤漁獲。同期間，未達整體效率的台灣拖網漁船占全體61%（212艘），其中包括76%（161艘）未達技術效率、46%（98艘）未達擁擠效率、70%（149艘）未達規模效率，其中有35艘處於規模報酬遞增下、114艘處於規模報酬遞減下。顯示導致漁船無效率之主要原因，依序為資源配置不合理，規模不當，以及擁擠現象。根據本文發現，進行效率分析研究時，對於非意欲產出與擁擠投入都應該予與特別重視。

This research applies Data Envelopment Analysis to cope with undesirable outputs (non-economic fish catch) and congestion inputs (overtime working) in order to explore the average efficiency of trawler during 1976 to 1987 in Taiwan.'Statistical Yearbook of Taiwan Bottom Fish Catch is used to fulfill the objective of this research. According to the empirical results, there is still a room to improve the Taiwan trawl fishery even though in the heyday. To be more precisely, Taiwan trawl fishery has 14% potential improvement each year with 86,221 kg potential outputs. In the same period, the Taiwan trawlers which did not reach the overall efficiency account for 61% (212 ships) of the total number. Specifically, percentages of the Taiwan trawler which could not reach the technical efficiency, congestion efficiency and scale efficiency are 76% (161 ships)、46%(98 ships) and 70% (149 ships) individually with 35 ships below IRS and 114 ships under DRS. As shown from the data, three main reasons for the inefficiency of fish boat are misallocation of resources, inappropriate scale and congestion.