摘要
通过对Laffon的模型进行了改进,将散户的效用函数改成了常系数绝对风险厌恶的负指数形式。Laffon的结论为:当θ1,θ2相距不远时,大户与散户都偏好混同均衡。而改进后的模型却找到了θ1,θ2的距离在一个具体的范围内,大户与散户才都偏好混同均衡。
By improving Laffon's model ,the utility function of less-stock holder is transformed to the negative exponent of the fixed coefficient absolute risk aversion. Laffon's conclusion is that when θ1 and θ2 are not far from each other, both abundant-stock holder and less-stock holder prefer pooling equilibrium. But the improved model finds that when θ1 and θ2 are within a specific distance, abundant-stock holder and less-stock holder prefer pooling equilibrium.
