This article presents the first experiment exploring the impact of debarments – the exclusion of colluding bidders – on collusion in procurement auctions. We find that debarments reduce collusion and bids relative to a market with no sanction. The deterrent effect of debarments increases in the length of the punishment. However, shorter debarments reduce efficiency and increase the bids of non-debarred bidders. This suggests that debarments that are too lenient may trigger tacit collusion among the bidders who remain in the market, thereby facilitating the very behavior they aim to deter.

中文翻译：

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采购拍卖中的禁止和勾结

本文介绍了第一个实验，探讨禁止（排除串通投标人）对采购拍卖中串通的影响。我们发现，与没有制裁的市场相比，取消资格减少了串通和投标。禁令的威慑效果随着惩罚的持续时间增加而增加。然而，较短的禁止资格会降低效率并增加未禁止投标人的投标。这表明，过于宽松的禁令可能会引发留在市场上的投标人之间的默契勾结，从而促进他们旨在阻止的行为。