Although algorithmic trading now dominates financial markets, some exchanges continue to use human floor traders. On March 23, 2020 the NYSE suspended floor trading because of COVID-19. Using a difference-in-differences analysis around the closure of the floor, we find that floor traders are important contributors to market quality. The suspension of floor trading leads to higher spreads and larger pricing errors for treated stocks relative to control stocks. To explore the mechanism, we exploit two partial floor reopenings that have different characteristics. Our finding suggests that in-person human interaction facilitates the transfer of valuable information that algorithms lack.

中文翻译：

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场内交易重要吗？


尽管算法交易现在主导着金融市场，但一些交易所继续使用人工场内交易员。2020 年 3 月 23 日，纽约证券交易所因 COVID-19 暂停场内交易。使用围绕场内收盘价的双重差分分析，我们发现场内交易者是市场质量的重要贡献者。相对于对照股票，场内交易的暂停导致处理股票的点差更高，定价误差更大。为了探索这种机制，我们利用了两个具有不同特征的部分楼层重新开放。我们的研究结果表明，面对面的人际互动有助于传递算法所缺乏的有价值的信息。