Policy simulation and analysis of replacing outdated productivity towards iron and steel industry

Replacing outdated productivity is an important goal of iron & steel industry during 11^th five-year period. Based on the policies summary, this paper builds a mixed approach integrating bottom-up into top-down model by using MCP algorithm, and then designs the corresponding replaced rate. Results of simulation shows that: (1)Replacing outdated productivity of small iron & steel enterprises is remedied by super large iron & steel enterprises. (2)Replacing outdated productivity has less influence on whole economy, but great influence on resource-based industries. (3)Directly saving energy is more remarkable, but the total effect of policies saving energy less. According these, some suggestion is set up. Scale effect is not only important way to replace outdated productivity, but also the important means to promote enterprises saving energy.