中国钢铁主营上市公司规模效率分析及其启示

本文阐述了采用距离函数计算规模效率的方法.应用Tim Coelli的投入导向DEA模型多阶段求解方法,计算出了我国钢铁主营上市公司2005年、2006年的规模效率.结果表明,年产粗钢小于200万吨的上市公司几乎都是规模无效的;年产粗钢小于300万吨的上市公司处于规模报酬递增状态;年产粗钢大于300万吨的上市公司大都是规模有效的;年产粗钢大于300万吨的上市公司的规模效率均值显著大于年产粗钢小于300万吨的均值;而且规模最大的几个公司连续两年都是规模有效的,它们处于规模报酬不变状态,其规模尚未大到进入生产函数的规模报酬递减区域.上述结论,有效地支持上市钢企通过整体上市、并购重组,扩大规模,提高规模收益,同时,支持我国钢铁产业不断提高产业集中度。

An Analysis on the Scale Efficiencies of Chinese Steel Producing Public Companies and Its Revelation

This paper illustrates calculating scale efficiencies via distance function method.Using inputoriented DEA models which are conducted by the multi-stage solution method introduced by Tim Coelli, the scale efficiencies of Chinese steel producing public companies in the year of 2005 and 2006 have been calculated.The results indicate that the companies produced less than 2 million tons of crude steel per year almost all were scale inefficient,the companies produced less than 3 million tons operated within the increasing returns to scale part of the production function,most of the companies produced more than 3 million tons were scale efficient,and the companies produced more than 3 million tons have bigger mean scale efficiency than the ones produced less than 3 million tons obviously,also the biggest scale companies are always fully scale efficient in the observed two years,they are not too big to be within the decreasing returns to scale part of the production function.The results given above support the Chinese steel producing public companies to expand scales to obtain scale returns by means of integral listing or mergers and acquisitions.And they support Chinese iron and steel industry to enhance its concentration ratio,too.