Assimetria na Transmissão de Preços e Poder de Mercado: o caso do mercado varejista de etanol no estado de São Paulo

Abstract:The presence of market power in fuel retailing has been a major concern in Brazil, motivating antitrust investigations as well as economic research. However, lack of appropriate data precludes the estimation of straight market power indicators, leaving the possibility of using price series to identify market power. The objective of this study is to identify the presence of market power at the retail of fuel ethanol in cities of different sizes. The method adopted consists in verifying if price increases and decreases are transmitted asymmetrically to consumers, assuming that more intense transmission of price increases is related to the presence of market power. Monthly wholesale and retail price series of ethanol for cities with different sizes located in São Paulo State, Brazil, were used. The results indicate the presence of market power, since retailers were able to transmit price increases more rapidly and more intensively than price decreases for most cities. Such results suggest that asymmetry in price transmission can be a useful analytical tool to investigate market power and that antitrust authorities must observe the retail concentration and the behavior in the fuel market in order to protect consumers.

摘要：燃料零售领域的市场势力问题始终是巴西社会关注的核心议题，进而推动了反垄断调查与相关经济研究的开展。然而，由于缺乏适配性数据，无法直接估算市场势力的直接指标，因此只能借助价格序列来识别市场势力。本研究旨在识别巴西不同规模城市燃料乙醇零售市场的市场势力存在状况。本研究采用的分析方法为验证价格涨跌向消费者的传导是否存在非对称性，并假设价格上涨的传导强度更高与市场势力的存在存在关联。本研究使用了巴西圣保罗州不同规模城市的乙醇月度批发与零售价格序列数据。研究结果显示，多数城市的零售商均能更快、更强地将价格上涨传导给消费者，而非价格下跌，这表明当地燃料乙醇零售市场存在市场势力。上述研究结果表明，价格传导非对称性可作为研究市场势力的有效分析工具，同时反垄断监管机构需关注燃料零售市场的集中度与市场主体行为，以切实保护消费者合法权益。