Adaptive expectations and stock market crashes

• 成果类型: Article
• 署名作者: Frankel, David M.
• 署名单位: Iowa State University
• 刊物名称: INTERNATIONAL ECONOMIC REVIEW
• ISSN/ISSBN: 0020-6598
• DOI: 10.1111/j.1468-2354.2008.00491.x
• 发表日期: 2008
• 页码: 595-619
• 关键词: price movements; volatility; MODEL; probability; representativeness; persistence; JUDGMENT; BEHAVIOR

摘要

A theory is developed that explains how stocks can crash. without fundamental news and why crashes are more common than frenzies. A crash occurs via the interaction of rational and naive investors. Naive traders believe that prices follow a random walk with serially correlated volatility. Their expectations of future volatility are formed adaptively. When the market crashes, naive traders sell stock in response to the apparent increase in volatility. Since rational traders are risk averse as well, a lower price is needed to clear the market: The crash is a self-fulfilling prophecy. Frenzies cannot occur in this model.