Theoretical and empirical study on cyclical company valuation Theoretical and empirical study on backpacker tourism Theoretical and empirical study of teachers' sense of gain Theoretical and empirical study on evolution of industrial organization Theoretical and empirical study of family farm development Theoretical and empirical study on commodity circulation space Theoretical and empirical study on marine fishery production in China Theoretical and empirical studying on television programming differentiation Theoretical and empirical research on intergroup relation Theoretical and empirical research on rural revitalization