A signal that identifies asset pricing bubbles would be valuable so investors could reposition their portfolios to weather the bubble, yet ex ante bubble identification has proven illusory. Arif and Sul (2024) study whether industry-level investment in net operating asset (NOA) accruals is an ex ante accounting-based signal that predicts bubbles. Using industry-level price run-ups across 49 countries, they find that NOA accruals predict a higher likelihood of a future crash, lower future returns, and larger analyst forecast errors, especially following run-up periods. The authors attribute these patterns to sentiment-driven overinvestment. My discussion summarizes the contributions of Arif and Sul's findings to the asset pricing bubbles, behavioral finance, and aggregate accruals literatures. I also outline empirical challenges faced by studies investigating bubbles and recommend approaches to further strengthen inferences. Finally, I propose opportunities for future research to integrate deeper accounting knowledge into bubble research.

中文翻译：

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泡沫的解释：Arif 和 Sul 的讨论 （2024）


识别资产定价泡沫的信号很有价值，这样投资者就可以重新定位他们的投资组合以度过泡沫，但事实证明，事前泡沫识别是虚幻的。Arif 和 Sul （2024） 研究了行业层面对净经营资产 （NOA） 应计项目的投资是否是预测泡沫的基于事前会计的信号。使用 49 个国家/地区的行业层面价格上涨，他们发现 NOA 应计项目预示着未来崩盘的可能性更高，未来回报更低，分析师的预测误差更大，尤其是在上涨期之后。作者将这些模式归因于情绪驱动的过度投资。我的讨论总结了 Arif 和 Sul 的发现对资产定价泡沫、行为金融学和总权应计文献的贡献。我还概述了调查气泡的研究面临的实证挑战，并推荐了进一步加强推理的方法。最后，我提出了未来研究的机会，将更深入的会计知识整合到泡沫研究中。