The threat of counterfeiting in competitive search equilibrium

This paper studies counterfeiting of bank notes in a monetary model under competitive search. The application of the refinement scheme proposed by Guerrieri et al. (2010) shows that there is no equilibrium with counterfeiting. However, due to the entry margin, counterfeiting poses a threat to the existence of a monetary equilibrium: there is no monetary equilibrium if the cost of producing counterfeits is low enough. Moreover, the threat of counterfeiting can generate an endogenous resalability constraint. An extension of the model is provided which allows the threat of counterfeiting to materialize, in that some buyers cannot observe the offers, and therefore search randomly. Counterfeit notes are produced by those buyers who randomly search.     

Impact of urban developments on the functional connectivity of forested habitats: a joint contribution of advanced urban models and landscape graphs

The impacts of urban growth on biodiversity vary according to the form and the intensity of urbanisation. However, there is a lack of knowledge about the consequences of the type of urban structure (e.g. monocentric vs polycentric), the shape of urban boundaries, the local density of residential development, on the habitats of wildlife species. In this context, this paper focuses on the relationship between forms of urbanisation and functional connectivity of ecological habitats. In the urban region of Besançon (eastern France), three emblematic protected species were selected to represent forest mammals. From the initial state describing current land cover, five prospective residential development scenarios were simulated, corresponding to the form currently most commonly found (e.g. compact development, transit-oriented development, polycentric development). For each scenario, we also simulate the volume of traffic on the road network to allow for the barrier effect of roads on habitat connectivity. Then, for each development scenario, we model the functional connectivity of habitats of the various target species using landscape graphs. Results show that compact city maintains more functional connectivity for all the species considered whereas urban sprawl leads to much more marked impacts. Moderately compact and regulated periurban scenarios have intermediate levels of impact. The transit-oriented development scenario produces specific impact values according to the species. An interesting point is that the decline in functional connectivity of forest habitats is more due to increased traffic than residential development proper. This outlines the relevance of integrated models for simulating both land use and transport at a fine scale.     

Graphical causal models and VARs: an empirical assessment of the real business cycles hypothesis

This paper assesses the empirical plausibility of the real business cycle view that shocks to real variables are the dominant sources of economic fluctuations and that monetary policy shocks play an insignificant role in determining the behavior of real variables. I reconsider the vector autoregressive model of King et al. (Am Econ Rev 81:819–840, 1991), but propose an alternative identification method, based on graphical causal models. This method selects the contemporaneous causal structure using the information incorporated in the partial correlations among the residuals. The residuals orthogonalization which follows and the study of the impulse response functions confirm the results of King et al. (Am Econ Rev 81:819–840, 1991): permanent productivity shocks are not the dominant sources of aggregate fluctuations in US economy. I would like to thank Peter Spirtes, Marco Lippi, and Clark Glymour for helpful comments on early versions of the paper. I am also grateful to Valentina Corradi for providing me with an updated version of the King et al. (1991) data set. The usual disclaimer applies.     

Effects of trade and agricultural policies on the structure of the U.S. tomato industry

Over the last few decades, accelerated growth of Mexican tomato imports to the United States has caused several trade disputes with U.S. growers. A data-driven approach was used to analyze trade flows in the tomato industry from 1970 to 2015 and all structural changes to policy interventions implemented during the same period were linked. Tests for endogenous breakpoints reveal that NAFTA and trade pricing policies are two of the main factors that caused structural changes in the tomato industry in 1992 and 1999. While U.S. agricultural policies sought to protect domestic tomato producers, they did not stop Mexican tomatoes from taking an important share of the U.S. market. Mexican imports to the United States, especially post-NAFTA, have a high explanatory power for U.S. domestic production.     

基于Java3D的建模与模型分解的研究与实现

Java3D是基于Java平台的、功能强大的面向对象的三维图形应用程序接口(API),利用Java3D能使三维模型变得更加快捷和清晰,也能实现对模型的自动分解。该文就如何应用Java3D建立模型并对存在的模型进行分解进行了初步的探讨,并提出了相应的实现方法。实例验证了该方法正确有效。     

The impacts of animal disease crises on the Korean meat market

Employing the error correction method and historical decomposition with direct acyclic graphs, we quantify the impacts of domestic and overseas animal disease crises on the Korean meat market. We have the following findings: (a) the market partially recovered 16 months after the domestic foot‐and‐mouth outbreak (FMD) in 2000, and 13 months after the domestic avian influenza (AI) incidents and the U.S. bovine spongiform encephalopathy (BSE) discovery in 2003; (b) animal disease outbreaks had differentiated impacts by disease type and at different levels of meat supply chain. Retail price margin increased relative to the farm and wholesale levels; and (c) disease outbreaks caused changes of dynamic interdependence between prices by meat type at different levels of meat supply chain.     

s=4的完全多部图K_(a_1n_1,a_2n_2,…,a_sn_s)的无符号Laplace特征多项式

文中计算得到了完全多部图K(n1,n2,…,n)t=Ka1n1,a2n2,…,asns当s=4时的无符号Laplace特征多项式。     

运行机理、政策依据与农村投行未来

分析定向放贷的农村投行模式运行机理、与农户融资相适宜的动态均衡作用机制、设计机理以及农村金融发展逻辑,以期为农村金融机构创新,提供先行先试的蓝本。寻求合适的金融供给模式,解决农户融资困境,特别是融资困境引起的投资乘数瓶颈,突破现有政策创新的局限及金融机构创新可持续发展的资金约束,探寻农村金融创新的可行性与适应性问题。     

Market Segmentation and Information Asymmetry in Chinese Stock Markets: A VAR Analysis

This study examines the market segmentation and information asymmetry patterns in Chinese stock markets. The recursive cointegration analysis confirms that each of six markets is not linked with other markets in the long run. Further, the result from data‐determined forecast error variance decomposition clearly shows that foreign investors in the Shanghai B‐share market are better informed than Chinese domestic investors in two A‐share markets and foreign investors in Shenzhen and Hong Kong markets over time. The finding challenges a widespread assumption of less informed foreign investors in the literature, but suggests that foreign investors could be more informed in emerging markets.