中文摘要：

中国上市公司的信息披露质量为何摇摆不定？论文以深交所A股上市公司2002—2010年的3549个年度观察样本为基础，实证研究发现：（1）近90％上市公司的信息披露质量在样本期间发生了上下波动，且绝大部分上市公司的信息披露质量都还有较大的提升空间；（2）上市公司信息披露质量的变化不影响其股票市场收益和公司市场价值，表明外部投资者不够关注公司的信息披露行为；（3）机构投资者持股、标准无保留的审计意见、高管薪酬、盈利能力等显著提升了上市公司的信息披露质量，而高管变更、董事会会议次数、负债水平等则显著降低了公司的信息披露质量。论文的研究结论对于规范上市公司的信息披露行为和促进资本市场健康发展具有重要的政策启示。

英文摘要：

Why does the quality of information disclosure blow hot and cold in Chinese listed companies？ Using a sample of 3549 firm-year observations of A-share companies listed in Shenzhen Stock Exchange during the period of 2002-2010, this study finds that （1） the quality of information disclosure has fluctuated during the sample period in nearly 90% firms, and has relatively huge rise space for most listed companies; （2） the quality change of information disclosure does not affect firms＇ stock market return and corporate market value, indicating that outside investors pay insufficient attention to information disclo- sure behaviors of listed companies; （3） institutional ownership, external auditing, management compensation, and firm profit- ability can significantly improve the quality of information disclosure, while executive turnover, board meetings, and leverage would significantly reduce the quality of information disclosure. Our findings have important policy implications for normaliz- ing listed companies＇ information disclosure behaviors and thus protecting the interests of investors and promoting the healthy development of capital market in China.