Robust political economy

This paper introduces the idea of “robust political economy.” In the context of political economic systems, “robustness” refers to a political economic arrangement's ability to produce social welfare-enhancing outcomes in the face of deviations from ideal assumptions about individuals' motivations and information. Since standard assumptions about complete and perfect information, instantaneous market adjustment, perfect agent rationality, political actor benevolence, etc., rarely, if ever actually hold, a realistic picture and accurate assessment of the desirability of alternative political economic systems requires an analysis of alternative systems' robustness. The Mises-Hayek critique of socialism forms the foundation for investigations of robustness that relax ideal informational assumptions. The Buchanan-Tullock public choice approach complements this foundation in forming the basis for investigations of robustness that relax ideal motivational assumptions. JEL Code B53, P16, P26     

THE MEANING OF FAILED REPLICATIONS: A REVIEW AND PROPOSAL

The welcome rise of replication tests in economics has not been accompanied by a consensus standard for determining what constitutes a replication. A discrepant replication, in current usage of the term, can signal anything from an unremarkable disagreement over methods to scientific incompetence or misconduct. This paper proposes a standard for classifying one study as a replication of some other study. It is a standard that places the burden of proof on a study to demonstrate that it should have obtained identical results to the original, a conservative standard that is already used implicitly by many researchers. It contrasts this standard with decades of unsuccessful attempts to harmonize terminology, and argues that many prominent results described as replication tests should not be described as such. Adopting a conservative standard like this one can improve incentives for researchers, encouraging more and better replication tests.     

An extended peer communities’ knowledge sharing approach for environmental governance

This paper is devoted to propose an approach to implement the idea of extended peer knowledge to environmental governance by means of engaging the «extended peer communities». Socially robust knowledge relies on transparency and citizen participation. These two underlying elements take the form of both assessment and post-assessment decision support systems. Initially, during the assessment process citizens and stakeholders are engaged in the framing, proposal of alternatives, and evaluation criteria. Then the analysts assessed the alternatives proposed by means of DSS. Then, in a second stage, the analysts inspired in the idea of transparency, gave back the assessment result to the «extended peer community» who were able to give their opinion regarding the results and suggest potential parametric changes that were used for sensitivity analyses. The authors explore the proposed extended peer communities’ knowledge sharing for environmental governance assessment using a case study applied to a sustainable mobility planning process carried out in Tenerife (Canary Islands). The results gathered highlight that this approach is of use for guaranteeing the robustness of complex environmental decisions under high levels of uncertainty.     

汇率与股价变动关系:基于汇改后数据的实证研究

研究我国2005年7月汇率制度改革后汇率与股市的关系及其传导机制,有助于深刻认识金融市场联动特征,对于防范金融市场风险和完善我国资本市场、外汇市场等的改革具有重要的理论和实践意义。本文实证发现了汇率和股价存在着长期均衡的协整关系;从长期来看,两者关系符合流量导向模型,上证指数受到汇率长期影响,从短期来看,股市和汇市存在着交互影响,汇率变化影响股指变动有时滞。运用滚动窗口的Granger检验和加入其他重要宏观变量的多变量协整检验,本文证明了这种长期关系具有较强的稳健性。进一步从板块指数与汇率的关系来看,房地产、金融、民航、石化、钢铁指数均与汇率存在着长期的协整关系,汇率变化是这些板块指数的Granger原因。最后,本文对实证结果做出分析并指出了相应的政策含义。     

Modeling cascade dynamics of railway networks under inclement weather

Understanding the cascade dynamics of delay propagation under inclement weather is crucial to proactive railway management. In this paper, we proposed a Switching Max-Plus System (SMPS) to model the delay propagation on railway networks, which extends the conventional MPS by incorporating multiple system matrices to capture the dynamic impacts of inclement weather. An algorithm based on the All-Paired Critical-Path (APCP) graph was developed to solve the SMPS, which calculates secondary delays without backtracking the precedent events. The proposed model and its solution algorithm were validated using discrete-time simulations on both artificial and empirical networks. The robustness of railway services was also analyzed using the concepts of vulnerability and diffusivity.     

影响自主创新的因素——基于BACE方法对中国省际数据的分析

经典估计贝叶斯平均(BACE)是最近由Sala-i-Martin等人提出的一种处理模型不确定性的方法,它可以在进行参数估计的同时给出各解释变量的稳健性指标,并且还能够按照解释能力的大小对众多的备选变量进行分类和排序.本文首次利用这一方法对可能影响中国自主创新的因素进行了全面的分析,在上百万次回归的基础上,我们得到的主要结果是:在事先列出的20个可能的解释变量中,本地区试验发展支出、人均GDP、贸易依存度、邻接地区试验发展支出对创新产出的解释能力最强,并且都具有良好的稳健性;贷款余额与GDP之比、外商直接投资与GDP之比、各地区科学研究支出、地方财政决算本级收入与GDP之比、邻接地区科学研究支出等五个变量对创新产出也有一定的解释能力.     

Bounds for Ratios of Posterior Expectations: Applications in the Collective Risk Model

This paper considers the collective risk model for the insurance claims process. We will adopt a Bayesian point of view, where uncertainty concerning the specification of the prior distribution is a common question. The robust Bayesian approach uses a class of prior distributions which model uncertainty about the prior, instead of a single distribution. Relatively little research has dealt with robustness with respect to ratios of posterior expectations as occurs with the Esscher and Variance premium principles. Appropriate techniques are developed in this paper to solve this problem using the k -contamination class in the collective risk model.     

Robustness of the air transport network

This paper presents a methodology for the detection of critical airports (those whose isolation would cause the largest losses in network connectivity) in the global air transport network (ATN), based on simulating an attack on selected ATN airports using different adaptive selection criteria. The performances of several node selection criteria are compared, together with a new criterion based on Bonacich power centrality. The results show that most critical airports can be detected with an adaptive strategy based on betweenness centrality. The detection of such airports may help the development of contingency plans to develop an appropriate response to any airport closure.     

Algorithms to compute CM- and S-estimates for regression

Constrained M-estimators for regression were introduced by Mendes and Tyler in 1995 as an alternative class of robust regression estimators with high breakdown point and high asymptotic efficiency. To compute the CM-estimate, the global minimum of an objective function with an inequality constraint has to be localized. To find the S-estimate for the same problem, we instead restrict ourselves to the boundary of the feasible region. The algorithm presented for computing CM-estimates can easily be modified to compute S-estimates as well. Testing is carried out with a comparison to the algorithm SURREAL by Ruppert.     

Robust multivariate analysis for mixed-type data: Novel algorithm and its practical application in socio-economic research

We propose a novel method and algorithm for the analysis and clustering of mixed-type data using a hierarchical approach based on Forward Search. In our procedure, the identification of groups is based on the identification of similar trajectories and then linked to very intuitive two-dimensional maps. The proposed algorithm can use different measures for the calculation of distance in the case of mixed-type data, such as Gower’s metric and Related metric scaling. A key feature of our algorithm is its ability to discard redundant information from a given set of variables. The practical usefulness of the algorithm is illustrated through two applications of high relevance for empirical economic research. The first one focuses on comparing different indicators of environmental policy stringency in different countries. The second one applies our procedure to identify clusters of countries based on information regarding their institutional characteristics.