Based On Dea Factors Of Production, Congestion Theory And Empirical Research

Research in input congestion is a new subject in Economics and Management Science.Input congestion is regarded as an awful waste of resource,namely that the improper increase of input will bring about not the increase of output but the decrease of it.Congestion is possible in actual production.Research on approaches to identify and measure congestion is greatly important because it is much more ordinary in Chinese industries.Based on achievements in research on congestion during the past thirty years,we build up a complete system to study congestion,including research on the causes of formation and approaches to measure congestion,on relations between congestion and return to scale,and on congestion improvements.FGL and BCSW are two major approaches to identify congestion.They are quite different from their definition of congestion,theoretical assumptions,and the motives to develop the models,so the result of both approaches is not the same.Since both approaches are used to identify congestion from the input perspective,we propose a new way to calculate output reduction amounts resulted from input congestion based on a new DEA model,which can also be used to identify input congestion from the output perspective.Congestion is the fourth kind of returns to scale besides increasing returns to scale(IRS),constant returns to scale(CRS),decreasing returns to scale(DRS).The existed methods are not suitable to evaluate the returns to scale when input congestion is present.It can be done by two perspectives,one is measured by the different efficiencies of FG model and ST model,the other is measured by means of calculating scale elasticity in production(ρ):ρ＞1,IRS;ρ=1,CRS;1＞ρ＞0,DRS;ρ＜0, Congestion.We also put forward three different methods and models to improve congestion based on different goals and tasks,including:(1) Maximizing the increment of output while keeping input fixed;(2) Achieving the furthest output improvement by the least decrease of labor input,when severe labor congestion is present;(3) Changing the input combination to suitable level to improve output.In the empirical research,Shanghai transportation equipment manufacturing industry(state-owned part) is considered as the object of study.Because the transportation equipment manufacturing industry is one of important industries related to the national economy and the Chinese people's livelihood,the state-owned part still maintains a major status.As one portion of Shanghai Advanced Manufacturing Industries,it is of great significance to measure and manage input congestion in Shanghai transportation equipment manufacturing industry(state-owned part).As a result,among seventeen years,only five yeas are technical efficient with input congestion,the other twelve years are both labor-congested and capital-congested.In addition,it is necessary to increase labor and decrease capital during 2005-2007 to obtain the maximal outputs.This research enriches the input congestion theory and expands its application, also it's a good reference for solving labor congestion problems to keep the stabilization of employment in China.