Empirical study of the social effects of changes in China's population age structure An empirical study of the social effects of changes in China's population age structure Empirical study of the economic effects of changes in China's population age structure An empirical study of the economic effects of changes in China's population age structure Empirical study on trial pattern change in the information age Empirical study on the effectiveness of China monetary policy Empirical study on the judicial regulation of new types of unfair competition in the internet Empirical research on the regional effects of monetary policy in China's transitional period Empirical study on the effects of corporate brand on product evaluation Empirical study on the reform of criminal pretrial procedure