中文摘要：

本文利用我国上市公司1993～2007年的9813个样本数据，采用数据包络分析方法探讨跨境双重上市能否提高公司的投资效率。研究结果表明，在A＋H双重上市公司所涉及的九个行业中，制造业、电煤水业、信息技术业、银行保险业、房地产业、社会服务业的A＋H公司的投资效率优于行业平均水平，占2007年底51家A＋H公司的68．6％；但果掘业、建筑业、交通运输业的A＋H公司的投资效率低于行业平均水平，占2007年底51家A＋H公司的31．4％。大部分A＋H公司的规模效率小于1但规模报酬递增，DEA表明这些公司应该继续扩大规模。大部分行业的上市公司（包括A＋H公司）的效率均值都逼近或超过0．9，但各行业公司间的效率值比较接近。

英文摘要：

Using the method of data envelopment analysis, we studied the data of 9813 listed companies in China from 1993 to 2007 to discuss whether cross-border dual listings can improve corporate investment efficiency. The results show that, in the nine industries concerned in A＆H dual-listing, the average investment efficiency of the A＆H companies belonging to the industries of manufacturing, electricity ＆ water ＆ coal, information technology, banking and insurance, real estate, social services, is higher than the corresponding industrial average level. The number of these A＆H companies account 68.6% of all the A＆H companies at the end of 2007 （51 companies）. However, the average investment efficiency of the A＆H companies belonging to the industries of excavating, construction, transportation, is lower than the corresponding industrial average level. The number of these A＆H companies account 31.4% of all the A＆H companies at the end of 2007 （51 companies）. Furthermore, the scale efficiency of most A＆H companies is less than 1 and the return to scale is increasing, which means that these companies should expand their scale. The average efficiency values of most industries （including A＆H companies） vary around 0.9, but average efficiency values of all the companies （including A＆H companies） in each industry are very adjacent.