Abstract:In a nevolving globalized production environment, how does every country avoid the external shock while sharing the benefits through participating in international division of labor? Some new insights might be obtained if it is studied from the perspective of value chain trade network that a country has with other countries. Based on world input-output data from 2000-2014, this paper finds global value chain trade network has some complex net work properties such as"small-world phenomenon" and "scale-free characteristics", and that the evolution of this whole network is agradual process. Then, the paper concludes that a country can increase its importance in the global value chain trade network by strengthening its intensity and extensity features, to weaken the impact from external shock. Finally, this paper verifies the above conclusions from both import (input) and export (output) directions: A country can increase the number of trade partners both upstream and downstream and reduce their trade intensity distribution concentration to make the world trade development layout broad and even, to weaken the shock of internal and external risk transmission and to increase the robustness of global value chain trade network.

Abstract:This paper establishes an MPEC model by using infinitely many differentiated classes of customers equilibrium method to analyze price strategy and network-size allocation strategy for a two-sided monopoly platform taking into account the choice behaviour of vertical differential two-sided users. Considering the multiple market equilibria problem, suply curve and demand curve are applied to analyzing the geometric features and feasible region of the multiple equilibria. The optimal price strategies are derived under both optimistic and pesimistic preferences for the multiple equilibria problem. The optimal network-size allocation strategies are also derived under these two preferences and the duality for optimistic price strategy and network-size allocation strategy is evidenced. In order to provide helpful suggestions and references for platform companies, assuming an initial network-size, the limit solution of the network-size trajectory iterative equation for solving equilibrium fixed-point problem of two-sided platform users is studied, and the optimal price strategies for a given network sizes are obtained.

Abstract:Multiple Lagrange multipliers in nonlinear programming usually lead to incorrect computation of shadow price of resources. This paper proves that the minimum Euclidean norm Lagrange multiplier is the shadow price. Moreover, an unconstrained optimization model is proposed to model the minimum Euclidean norm Lagrange multiplier. Finally, asubgradient-based algorithm is proposed to compute the shadow price. This algorithm is sub-linearly convergent, and the computational time grows linearly with the number of constraints and variables.

Abstract:Is urban sprawl conducive to improving urban productivity? The paper explains theoreticaly the intrinsic mechanism of how urban sprawl affects productivity from urban scale and urban population density, and then, based on the night light data of 104 cities in the Yangtze River Economic Belt from 202-2013, empirically studies the productivity effects of urban sprawl. The main conclusions are as follows: 1)Urban sprawl has a significant negative impact on the productivity of the Yangtze River Economic Belt, which means that urban sprawl and low-density expansion hinder the productivity of the Yangtze River Economic Belt. 2)The regional study finds that urban sprawl has negative effects on urban productivity in eastern, central and western regions, has the minimum impact on productivity in the east, and has a greater impact on productivity in the central and western regions. 3)The research of the branch industry finds that urban sprawl reduces secondary productivity while significantly increasing the productivity of the service sector. 4)The Durbin model with spatial spillover efects tells that the direct and indirect effects of urban sprawl on productivity are significantly negative, and that the indirect effects are much greater than the direct, which means urban sprawl has significant spatial spilover effects on the urban productivity of the Yangtze River Economic Belt.

Abstract:Existing research has not reached a consensus on the relationship between threat situations and individual prosocial behavior. Thus, this study takes novel coronavirus epidemic as a specific research situation and fills a gap in previous research from two perspectives: The time and the type of the threat situation. This study takes in-group identity and other-focused attention as intermediary mechanisms and proposes the dualpathway formationmechanism that affects individuals' willingness to donate and relevant moderator variables in the context of major public threats. The following findings are obtained for public threat scenarios, such as the novel coronavirus epidemic, facing both donors and recipients. 1) There is no significant difference in the impacts of epidemic severity at the location of the potential donors on their willingness to donate. 2) The opposite intermediary effect of in-group identity and other-focused attention masks the impact of epidemic severity at the location of the potential donors on their willingness to donate. The severity of local epidemic enhances individuals' in-group identity and then positively affects their wilingness to donate. On the other hand, it reduces the individuals' other-focused attention and then weakens their willingness to donate. 3) Regional cultural orientation moderates the positive intermediary effect of in-group identity and the negative intermediary effect of other-focused attention. Specifically, compared with partial individualism, when regional cultural orientation is partial colectivism, the positive impact of local epidemic severity on in-group identity can be enhanced and negative impact on other-focused attention can be reduced.

Abstract:Under the uncertain demand environment facing both exogenous and endogenous factors, by establishing a decision model for production input, government incentives, and enterprise production scale, based on the research on the value expressions of production inputs of enterprises, the mechanism of production inputs, government incentives, and decision-making on enterprise production scale is analyzed, and the critical value equation, optimal production scale, and optimal government incentives are analyzed. The study shows: 1)Flexible enterprises can optimize the production scale according to changes in market demand, with reference to capitalized future production scale, government incentive cash flow, abandonment option value, and demand change option value, etc; 2) When the enterprise unit time income stream meets at a certain level, there exists an optimal product ion scale equation and an optimal government incentive equation and their corresponding threshold equations; 3)There is a close relationship between production input, government incentives, and enterprise production scale, and flexible enterprises can dynamically adjust production accordingly. In addition, comparisons with exogenous models verify the adaptability of the model. Therefore, it can be used as a reference to strengthen the production scale decision of enterprises in an environment of uncertain demand.

Abstract:This paper models economic policy uncertainty into venture capitalists' decision-making process, proving that economic policy uncertainty reduces venture capitalists' risk-taking both directly and indirectly. Using the matched data of China's economic policy uncertainty and venture capital investments over the period of 1996~2016, this paper empirically examines the impact of economic policy uncertainty on risk taking and provides suportive evidence for the hypotheses. It is found that economic policy uncertainty negatively impacts risk taking and reduces venture capital investments into early-stage and high-tech entrepreneurial firms. Further, the exit success performs a mediating effect between economic policy uncertainty and risk-taking. Specifically, as the economic policy uncertainty increases, the number of venture capitalists' successful exits from entrepreneurial firms through IPO or M&A declines. Venture capitalists are less able to successfully exit, or they have to hold shares for a long time and receive low returns even though they managed to successfully exit from entrepreneurial firms with increasing economic uncertainty, so that they are less inclined to take risks. The results suggest that providing and maintaining stable economic policies are crucial to guide venture capital towards early-stage and technological firms.

Abstract:This study reviews the application and funding of projects in the economic science of the National Natural Science Foundation of China during the 13th Five-Year Plan period (2016~2020). A systematic analysis of funding characteristics and structural changes from the perspectives of project leaders, supporting organizations，and subject areas is presented. Taking the agricultural and forestry economics and management subject as an example, the development of research topics is discussed and an outlook for future funding management of the economic science is provided.