Does advertising help consumers to find the products they need or push them to buy products they don’t need? In this paper we study the heterogeneous effects of advertising on consumer mistakes in the market for mortgage refinancing and quantify the resulting overall effect on the net present value of mortgage debt. Mortgage borrowers frequently make costly refinancing mistakes by either refinancing when they should wait, or by waiting when they should refinance. We assemble a novel data set that combines a borrower’s exposure to direct mail refinance advertising and their subsequent refinancing decisions. Even though borrowers would lose on average $1229 by refinancing, the average monthly exposure of 0.13 refinancing direct mail advertisements reduces the expected net present value of mortgage payments on average by $7 each month, because borrowers who should refinance are targeted by advertisers and more responsive to advertising. A counterfactual advertising policy that redirects all advertising to borrowers who should refinance would increase the gain in borrower welfare to $36.

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消费者的错误和广告：抵押贷款的情况

广告是否可以帮助消费者找到所需的产品，或者促使他们购买不需要的产品？在本文中，我们研究了广告对抵押贷款市场中消费者错误的异质影响，并量化了由此产生的对抵押债务净现值的整体影响。抵押借款人经常通过在应等待的时间进行再融资或在应等待的时间进行再融资而犯下代价高昂的再融资错误。我们组装了一个新颖的数据集，该数据集将借款人对直接邮件再融资广告的曝光度及其随后的再融资决定结合在一起。即使借款人因再融资而平均损失1229美元，但平均每月0.13笔直接邮寄广告的再融资暴露仍会减少抵押贷款的预期净现值平均每月增加7美元，这是因为应该再融资的借款人是广告客户的目标，并且对广告的反应更快。一项反事实广告政策会将所有广告重新定向到应该再融资的借款人，这将使借款人的福利增加到36美元。