Trust, a cornerstone of economic development, is promoted within religions. In a randomized controlled trial, we examine how trust and trustworthiness vary across religions (Christianity and Islam), religiosity, and atheists/agnostics in the United States. Three novel findings emerge. First, Christians are trusted more than Muslims and nonbelievers, which is due to a Christian ingroup bias––Christians trust Christians more than they trust Muslims and nonbelievers, while Muslims and nonbelievers trust all groups the same. Second, religiosity matters to trust. Religious people trust those of higher religiosity more, but only if they are of the same religion. In contrast, nonbelievers trust people of higher religiosity less. Third, trustworthiness among nonbelievers is somewhat lower than that of the religious, especially toward Christians. We speculate that the lower reciprocity originates in the prejudice toward nonbelievers. Our results may help explain discrimination against Muslims and nonbelievers, given that discrimination often originates in distrust.

中文翻译：

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美国基督徒，穆斯林和无神论者/不可知论者的信任与信赖

信仰是宗教发展中经济发展的基石。在一项随机对照试验中，我们研究了在美国，不同宗教（基督教和伊斯兰教），宗教信仰和无神论者/不可知论者之间的信任度和可信度是如何变化的。出现了三个新颖的发现。首先，基督徒比穆斯林和非信徒更受信任，这是由于基督徒在群体中的偏见-基督徒对基督徒的信任比对穆斯林和非信徒的信任要多，而穆斯林和非信徒对所有群体的信任都一样。第二，宗教信仰很重要。宗教人士对宗教信仰较高的人更加信任，但前提是他们属于同一宗教。相比之下，非信徒对宗教信仰较高的人的信任就会减少。第三，非信徒之间的信任度比宗教信仰的信任度低，尤其是对基督徒的信任度。我们推测，较低的互惠源于对非信徒的偏见。鉴于歧视通常源自不信任，因此我们的结果可能有助于解释对穆斯林和非信徒的歧视。