This study presents an agent-based model of capital markets by adopting simple trading rules for bounded rational agents who maintain different expectations regarding a tipping point at which price starts to change its direction from rising (falling) to falling (rising). The effect of herding behavior on the volatility of stock market prices and the rate of return to the herding group are investigated by dividing agents into one or more groups. Herding behavior by a group of agents leads to high market volatility and high return for the agents in the group. Maximum rate of return is reached when the group size is approximately 3% of the total number of agents. This finding is consistent with the actual degree of herding behavior in markets found by empirical studies. However, the rates of return decrease when the group size exceeds 3%, and the premium of the herding group tends to disappear when the group size reaches a certain level (20%) compared with that of non-herding groups. Reducing the number of groups (or increasing the average size of the herding groups) leads to high price volatility.

这项研究通过为有界理性代理人采用简单的交易规则，提出了一种基于代理人的资本市场模型，这些有理智的代理人对临界点保持不同的期望，在临界点上价格开始改变其从上升（下降）到下跌（上升）的方向。通过将代理商分为一个或多个组来研究羊群行为对股票市场价格波动和羊群收益率的影响。一组代理商的羊群行为导致该组代理商的高市场波动性和高回报。当组的规模约为座席总数的3％时，可以达到最大的回报率。这一发现与通过经验研究发现的市场中羊群行为的实际程度是一致的。但是，当小组人数超过3％时，回报率会下降，与非放牧组相比，当组规模达到一定水平（20％）时，放牧组的溢价趋于消失。减少群体数量（或增加羊群的平均规模）会导致价格高波动。