企业性质、公司治理与股价同步性

Corporate Nature,Corporate Governance and Stock Price Synchronization

以2008-2016年A股上市公司为样本经实证分析得出,第一大股东持股比例与股价同步性的关系是非线性的。当企业为国有企业时,该非线性关系为U型;当企业为私营企业时,该非线性关系为倒U型。当企业为国有企业时,两权分离度(控制权和现金流权)与股价同步性负相关;而在私营企业中,两权分离度与股价同步性正相关。整体上看,两职合一增加了股价中企业信息的含量,降低了股价同步性,但这一作用在国有企业中并不明显。无论在是国有企业还是私营企业中,股权制衡制度都可以有效降低股价同步性,且私营企业中股权制衡作用效果更佳。独立董事占比与股价同步性的关系并不显著。

Based on an empirical analysis of A-share listed companies from 2008 to 2016, the relationship between shareholding ratio of the largest shareholder and stock price synchronization is nonlinear, and when the company is a state-owned enterise, the nonlinear relationship is U-shaped; when the company is a private enterprise, the nonlinear relationship is inverted U-shaped. When the enterprise is a state-owned enterprise, the separation of powers （control rights and cash flow rights） is negatively related to the synchronization of stock prices; while in the private sector, the separation of powers is positively related to the synchronization of stock prices. On the whole, the integration of the two positions has increased the content of corporate information in the stock price and reduced the synchronization of stock prices, but this effect is not obvious in state-owned enterprises. Whether it is a state-owned enterprise or a private enterprise, the system of shareholding cheeks and balances can effectively reduce the synchronization of share prices, and the effect of shareholding cheeks and balances in private enterprises is better. The relationship between the proportion of independent directors and the synehrony of stock prices is not significant.