中文摘要：

市场时机资本结构理论认为企业在股票价格高估时发行股权融资，低估时选择回购股票或发行债务融资，当前资本结构是企业过去融资发行市场时机的累积结果。目前的实证研究主要基于市值账面比（M／B）指标作为市场时机代理变量，然而这一指标引起学者们很大争议，研究结论缺乏可靠性。本文根据我国资本市场实际特征选择股票换手率作为市场时机代理变量，实证检验了市场时机与外部融资方式选择的关系，以及对资本结构动态变动的综合影响。研究结论显示，换手率在企业权益融资中具有重要作用，换手率较高时企业选择发行更多的股权融资，并对资本结构变动具有显著的负向影响。这表明我国上市公司确实存在着融资选择的市场时机效应。

英文摘要：

The market timing theory of capital structure suggests that firms are more likely to issue equity when their market values are high, and repurchase equity or issue debt when their market values are low. So, the current capital structure is the cumulative outcome of past attempts to time the equity market. The current empirical study is based on the market-to-book as the market timing variables. However, it has the great controversy about market-to-book, and the conclusion is lack of reliability. According to China＇s capital market characteristics, this paper chooses the shares turnover as the market timing variables to examine empirically the correlation between market timing and exterior financing translations, and the effects on leverage change. The evidence shows that the shares turnover has the important functions in equity issuing of listed companies, and the company is likely to issues more equity when the shares turnover are high. We find the negative relations between shares turnover and change of leverage. We also find the market timing effects of financing translations in Chinese listed companies.