Impact of state-dependent oil price on US stock returns using local projections

In this paper, we investigate the impact of oil prices on both aggregate and industry US real stock returns over the period 1973–2017. The empirical analysis contributes to the related literature introducing a state-dependent oil price (high and low) and the local projections approach. Our main finding is that, depending on the nature of the shock and industry, the negative effects of oil price shocks become exacerbated -and the positive effects get moderated- if oil prices are already high.     

The Effect of Endogenous Regulation on Telecommunications Expansion and Efficiency in Latin America

I examine the effect of reform on telecom performance using a second-generation regulatory framework index and panel data techniques to test how regulatory governance affected sector performance in 22 Latin American countries during the period 1980–1997. Sound regulatory governance in telecommunications has a positive impact on network expansion and efficiency, in both the static and dynamic specifications. Openness of markets to competition and divestment of former state-owned telco operators also contributed positively to better sector performance. The dynamic specification shows that past performance has its own strong effect on present (and perhaps future) performance.     

Neutrality in arrow and other impossibility theorems

Summary. Although not assumed explicitly, we show that neutrality plays an important role in Arrow and other impossibility theorems. Applying it to pivotal voters we produce direct proofs of classical impossibility theorems, including Arrow's, as well as extend some of these theorems. We further explore the role of neutrality showing that it is equivalent to Pareto or reverse Pareto, and to effective dictatorship for non-null social welfare functions satisfying the principle of independence of irrelevant alternatives. It is also equivalent to Wilson's Citizens' Sovereignty--which is related to the intuition that symmetry over alternatives makes social preference depend only on citizens' preferences. We show that some of these results are more fundamental than others in that they extend both to infinite societies and to considerably smaller domains of preferences. Finally, as an application of Arrow's theorem, we provide a simple proof of the Gibbard-Satterthwaite theorem.Received: 13 April 2000, Revised: 6 December 2002, JEL Classification Numbers: D71, C70.I thank Salvador Barberá, Luis Corchón, Cesar Martinelli, Eric Maskin, Tomas Sjöström, Ricard Torres, José Pedro Ubeda, and an anonymous referee for feedback. The proofs of Arrow's theorem and two Wilson's theorems come from a note I wrote in 1987 at Universitat Autónoma de Barcelona (Ubeda [16]). In 1996 Geanakoplos [7] wrote a proof of Arrow's theorem similar but not identical to mine. All work in this paper is independent of his.     

农民养老问题亟待解决

农村现行的家庭养老、土地养老、集体养老正在弱化,巩固家庭养老的基础地位,强化土地保障功能,辅之以社区扶持,推行多层次养老保险,符合中国国情和农村生产力发展水平,是解决农村养老问题的必然选择.     

Mining and Social Movements: Struggles Over Livelihood and Rural Territorial Development in the Andes

Social movements have been viewed as vehicles through which the concerns of poor and marginalized groups are given greater visibility within civil society, lauded for being the means to achieve local empowerment and citizen activism, and seen as essential in holding the state to account and constituting a grassroots mechanism for promoting democracy. However, within development studies little attention has been paid to understanding how social movements can affect trajectories of development and rural livelihood in given spaces, and how these effects are related to movements’ internal dynamics and their interaction with the broader environment within which they operate. This paper addresses this theme for the case of social movements protesting contemporary forms of mining investment in Latin America. On the basis of cases from Peru and Ecuador, the paper argues that the presence and nature of social movements has significant influences both on forms taken by extractive industries (in this case mining) and on the effects of this extraction on rural livelihoods. In this sense, one can usefully talk about rural development as being co-produced by movements, mining companies, and other actors, in particular the state. The terms of this co-production, however, vary greatly among different locations, reflecting the distinct geographies of social mobilization and of mineral investment, as well as the varying power relationships among the different actors involved.     

江苏居民收入分配差距及其治理分析

改革开放以来,江苏居民收入普遍提高,人民生活得到很大改善,但近年来居民收入开始出现差距并且日益扩大,已成为影响社会稳定和经济发展的重要问题。文章首先分析了江苏居民收入分配的现状,然后剖析了影响居民收入分配差距过大的成因,在此基础上提出了防止居民收入差距过大的治理对策。     

混合拉曼/EDFA放大器及其在DWDM中的应用

本文综述了混合拉曼／掺饵光纤放大器（HFA）的工作原理，结构和特点，介绍了4类HFA基本结构及其实验结果，并通过介绍近年来各类HFA在密集波分复用（DWDM）系统中的应用表明了HFA在带宽，增益和噪声特性方面的优点。     

Testing for Unit Roots with Breaks: Evidence on the Great Crash and the Unit Root Hypothesis Reconsidered

Nelson and Plosser (1982), in a classic paper, failed to find strong evidence against the null hypothesis of a generating process with a unit autoregressive root for thirteen US macroeconomic time series. Perron (1989) claimed that such evidence was available for a majority of these series if the alternative hypothesis was of trend stationarity with a break in 1929. Zivot and Andrews (1992) treated the break date as endogenous, then finding strong evidence agcainst the null for a minority of these series. Our own analysis extends theirs by permitting a break under the null as well as the alternative hypothesis, and allowing for the sequential nature of the testing. Our empirical findings complete the circle. We find no strong evidence against the unit root hypothesis for any of the thirteen Nelson–Plosser series.     

Scarcity and appropriative competition

This paper formalizes the commonsensical hypothesis that resource scarcity causes a large allocation of time and effort to appropriative competition. Our main innovation is to model explicitly the positive intertemporal effect of consumption on the probability of survival. The critical assumption is that this effect becomes stronger as resources become scarcer. We also show that anticipated future resource abundance increases the incremental value of survival and, consequently, amplifies the current allocation of time and effort to appropriative competition. Interestingly, if resources are currently scarce, then larger anticipated future abundance can cause a big enough increase in the time and effort allocated to appropriative competition to result in a decrease in the sum of current and expected future utility, a “paradox of anticipated abundance”.