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An Epidemiological Approach To Opinion And Price-Volume Dynamics, Dong Hong, Harrison G. Hong, Andrei Ungureanu

Research Collection Lee Kong Chian School Of Business

We develop a simple and tractable model of opinions and price-volume dynamics based on a word-of-mouth communication process widely used in epidemiology. Risk-averse investors have different opinions depending on whether they heard the news from a friend. Opinions initially diverge and then converge over time as news spreads, which leads to price adjustment and trading volume. News released to many leads to an expected difusion rate (the change in the fraction of investors with the news) that declines with time. But news initially released to few leads to an expected diffusion rate that initially increases in time and only then …