Changes in firms’ warranty payments are informative signals that enable investors to form timely expectations about potential changes in product quality. The authors’ survey shows that warranty payments affect potential investors’ product quality assessments and stock investment likelihood. Their quantitative analysis reveals an asymmetric stock market reaction: unanticipated increases in warranty payments (which signal quality “losses”) lower stock returns but unanticipated decreases do not affect stock returns. Two important factors moderate this relationship. First, boosting advertising spending attenuates the negative stock return effect of unanticipated increases in warranty payments. Second, unanticipated decreases in warranty payments, which signal quality “gains”, translate into higher stock returns when the industry has become less concentrated. Interestingly, changes in R&D spending do not moderate investors’ response to unanticipated increases or decreases in warranty payments. The authors advise firms to use advertising to lessen the harm from warranty payment increases and to strongly communicate warranty payment decreases in the face of intensified competition. The authors also caution that offering warranties in general does not ensure greater firm value as declining quality firms that myopically offer warranty programs experience lower firm value than those that do not provide warranties.

公司保修付款的变化是信息性信号，使投资者能够对产品质量的潜在变化形成及时的预期。作者的调查表明，保修付款会影响潜在投资者的产品质量评估和股票投资可能性。他们的定量分析揭示了一种不对称的股市反应：保修付款的意外增加（这表明质量“损失”）降低了股票回报，但意外的下降不会影响股票回报。有两个重要因素缓和了这种关系。首先，增加广告支出减弱了保修付款意外增加的负面股票回报效应。其次，保修付款意外减少，这标志着质量“提高”，当行业集中度降低时，转化为更高的股票回报。有趣的是，研发支出的变化并没有缓和投资者对保修付款意外增加或减少的反应。作者建议公司使用广告来减少保修付款增加带来的危害，并在竞争加剧的情况下强烈传达保修付款减少。作者还警告说，一般而言，提供保修并不能确保更高的公司价值，因为短视提供保修计划的质量下降的公司比不提供保修的公司经历的公司价值更低。作者建议公司使用广告来减少保修付款增加带来的危害，并在竞争加剧的情况下强烈传达保修付款减少。作者还警告说，一般而言，提供保修并不能确保更高的公司价值，因为短视提供保修计划的质量下降的公司比不提供保修的公司经历的公司价值更低。作者建议公司使用广告来减少保修付款增加带来的危害，并在竞争加剧的情况下强烈传达保修付款减少。作者还警告说，一般而言，提供保修并不能确保更高的公司价值，因为短视提供保修计划的质量下降的公司比不提供保修的公司经历的公司价值更低。