Metafrontier production and technical efficiency of shrimp farming in the States of Ceará and Rio Grande do Norte

Abstract In the Northeast of Brazil, the shrimp farming has achieved high level of technical efficiency; however, these advances have not happened homogenously among producing states. This study aims to analyze the technological differences of shrimp production occurring among the two major producer states of this commodity, Ceará and Rio Grande do Norte, 2011. In order to perform this, we applied the technological meta-frontier model proposed by Battese, Rao and O’Donnell, which aims to estimate an envelope function of the production stochastic frontier of the two states. Production and management data were extracted from the 2011 Shrimp Farming Census, conducted by the Brazilian Association of Shrimp Farming (ABCC), constituted of 100 farms in Ceará and 112 in Rio Grande do Norte. The results showed that, in average terms, Ceará was more technically efficient (ET) than Rio Grande do Norte, and theaverage area of ponds had higher impact over Ceará’s ET, while the number of hired workers had higher impact over Rio Grande do Norte’s ET.

摘要 巴西东北部的虾类养殖业已达到较高的技术效率水平，但各养殖州之间的技术进步并不均衡。本研究旨在分析2011年巴西两大虾类主产州——塞阿拉州（Ceará）与北里奥格兰德州（Rio Grande do Norte）的虾类生产技术差异。为此，本研究采用了由Battese、Rao与O’Donnell提出的技术元前沿模型（technological meta-frontier model），该模型用于估算两个州的生产随机前沿包络函数。本研究的数据取自巴西虾养殖业协会（Brazilian Association of Shrimp Farming，ABCC）开展的2011年虾类养殖普查，该普查涵盖塞阿拉州的100家养殖场与北里奥格兰德州的112家养殖场。研究结果显示，从平均水平来看，塞阿拉州的技术效率（Technical Efficiency，ET）高于北里奥格兰德州；其中，养殖塘平均面积对塞阿拉州的技术效率影响更为显著，而雇佣工人数量对北里奥格兰德州的技术效率影响更大。