We use a natural field experiment to estimate the causal effect of race on discretionary favours in the marketplace. Test customers are randomly assigned to board public buses with no money to purchase a fare, leaving the bus driver to voluntarily decide whether to offer them a free ride. Based on 1,552 transactions, we uncover strong evidence of racial bias: bus drivers were twice as willing to let white testers ride free as black testers (72% vs. 36% of the time). Signals of wealth and patriotism improve minority testers’ outcomes. Our results show that white privilege extends to unregulated daily interactions.

中文翻译：

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搭便车的颜色

我们使用自然现场实验来估计种族对市场上可自由支配的优惠的因果影响。测试客户被随机分配到没有钱购买车费的公共巴士上，让巴士司机自愿决定是否为他们提供免费乘车服务。基于 1,552 笔交易，我们发现了种族偏见的有力证据：公交车司机让白人测试员免费乘坐的意愿是黑人测试员的两倍（72% 对 36%）。财富和爱国主义的信号改善了少数族裔测试者的结果。我们的结果表明，白人特权延伸到不受监管的日常互动。