The Research on the Measurement of Inefficiency Investment Degree of China's GEM Listed Companies

October 30, 2009, the GEM officially launched, which was an important step to improve China's capital market system. For the listed companies, investment efficiency is one of the three major investment decisions. Due to the short period of study, the research area is less related to the GEM listed companies. Theoretically, in the perfect market described by Modigliani and Miller, investment decisions are totally determined by investment opportunities, regardless of the impact of other factors. But in the real world of imperfections, agent problems and information asymmetry can lead to inefficient investment. From the point of view of the Principal-agent Theory and the Free Cash Flow hypothesis, the principal-agent conflict between the shareholders and the senior managers leads to the fact that the senior managers maximize their own utility and put the free cash flow into the project whose net present value is not greater than zero. In the information asymmetry theory and financing constraints hypothesis, the information asymmetry between the company and the external investors will make it difficult for external investors to make an accurate valuation of the company. To reduce the loss of the risk, they tend to underestimate the value of the company, so the financing cost of company in the capital market have been raised, and when the internal cash is in the shortage, the senior managers do not want to choose external financing with high cost to meet the investment need, to give up investment in project whose the net present value is larger than zero, resulting in underinvestment. At the level of empirical analysis, this paper chose the financial data and market transaction data of the GEM listed companies from 2010 to 2015 to study. Based on the Expected Investment Model of Richardson (2006), this paper used the generalized difference moment method (GMM) to estimate the expected additional investment, with the amount of investment, resulting in overinvestment and underinvestment. The conclusion is that there are overinvestment behavior and underinvestment behavior of the GEM listed companies in the research period. This paper measured the level of inefficient investment of listed companies on the GEM, so that the micro-subject in the multi-level capital market can clearly define the direction of its own need. In addition, we also hope to provide empirical reference for the policy makers in the formulation of relevant policies to create a good market environment for listed companies.