Research On The Mechanism Of "Learning By Doing" Effect On GTFP Of China's Manufacturing Industry

China's economic level has improved significantly since the reforms were opened,but at the same time,energy and environmental issues are becoming increasingly prominent and limiting the development of the economy.It has become the consensus of the current academic circles to give attention to energy and environmental issues while improving the level of economic growth.Many scholars have incorporated energy consumption and environmental pollution into the measurement framework of TFP and they put forward the Green Total Factor Productivity(GTFP),an indicator for measuring economic performance under the concept of green development.Manufacturing industry is an important component of China's economic system.In the context of economic restructuring,China's manufacturing industry is facing the pressure to maintain growth and the constraints of energy environment while maintaining high-speed growth.In order to solve these two bottlenecks,its GTFP should be studied under the framework of green development.In this paper,the SBM-ML model with variable returns to scale is used.Firstly,the green total factor productivity index ML of China's manufacturing industry is calculated,and then it is divided into two parts: the green technology efficiency index(EC)and the green technology progress index(TC).Thus we know the current situation of green development of manufacturing industry and the main sources of GTFP promotion.The results show that From 2007 to 2016,the annual growth rates of green total factor productivity,green technology efficiency and green technology progress in China's manufacturing industry are 18.1%,9.1% and 11.2% respectively,which shows that both green technology efficiency and green technology progress have played an important role in the development of China's manufacturing industry,while the later plays a slightly greater role.However,the annual change trend of GTFP among varioussub-industries is relatively large,which indicates that the green development level of various industries is quite different.In addition,this paper uses panel data of China's manufacturing sub-sectors from2007 to 2016,and uses the cumulative sales value of the industry as a measure of the "learning by doing" effect.For the first time,it explores the impact of the "learning by doing" effect on China's manufacturing GTFP and its decomposed parts GEC and GTC under the framework of green development.The results show that the cumulative sales value of the industry has a significant positive impact on the GTFP,GEC and GTC during the study period,and for every 100% increase in the cumulative sales value,GTFP,GEC and GTC increase by 0.44%,0.116% and 0.17% respectively,which indicates that the "learning by doing" effect can effectively promote the promotion of GTFP,and this promotion effect is realized by improving the technical efficiency and technical progress level at the same time,while the latter effect is slightly larger.All the above conclusions are verified by the robustness test results of measuring "learning by doing" effect by using the cumulative added value of the industry.From the regression coefficient,it can be found that the development of China's manufacturing industry has reached a stage where the "learning by doing" effect is relatively weak.Therefore,in order to promote the green development of China's manufacturing industry,in addition to playing the role of the "learning by doing" effect,we should also look for policy power points from other factors.