在证券市场上，任何一位投资者都是根据信息进行投资的，而各投资者同时获得充分完全信息是不可能的，即有效市场理论是不符合实际的。比较现实的假设是公司内部人员比公司外部人员更多地了解公司内部信息，公司管理人员，比公司内部员工更多地掌握公司内部信息。凡此种种，说 In the securities market, any investor invests on the basis of information. It is impossible for all investors to obtain full and complete information at the same time. That is to say, effective market theory is not realistic. A more realistic assumption is that insiders know more about the company’s internal information than outsiders, and that company managers have more information about the company than insiders. All these say