In 2015, a supposed bid-rigging cartel that operated in the Brazilian implantable cardiac devices market was announced and public authorities began to investigate it. This paper evaluates if there is systematic correlation between the bids that are placed by competitors in the sealed phase of procurement auctions, which is a situation that may suggest coordinated and fraudulent behaviour. By applying Moran’s I statistic to the residuals of controlled bid regressions and using a novel and public database, we show that the bids that were placed by the investigated companies have positive and statistically significant autocorrelation. In addition, when we separate the data into two subperiods, namely, the period in which the cartel probably existed (2005–2015) and the period in which the cartel probably did not exist due to the conclusion of a leniency agreement (2015–2017), the Moran’s I statistic only points to autocorrelation in the first sub-sample. Our result has remained robust when we eliminate transitional periods and use alternative economic screens. Finally, we show the main practical advantages and disadvantages of the implementation of the screen based on Moran’s I statistic.

2015年，宣布了一个在巴西植入式心脏设备市场运作的假想的卡特尔卡特尔组织，政府当局开始对其进行调查。本文评估了竞争者在采购拍卖的封闭阶段下的投标之间是否存在系统的相关性，这种情况可能暗示了协调和欺诈行为。通过应用莫兰的我统计受控出价回归的残差并使用新颖的公共数据库，我们显示，被调查公司下的出价具有正向和统计上显着的自相关。此外，当我们将数据分为两个子时段时，即可能存在卡特尔的时期（2005-2015年）和由于达成宽大处理协议而可能不存在卡特尔的时期（2015-2017年） ），Moran's I统计仅指向第一个子样本中的自相关。当我们消除过渡期并使用其他经济指标时，我们的结果仍然很稳健。最后，我们展示了基于Moran的I统计量实现屏幕的主要实际优缺点。