An Updated Ranking of Academic Journals in Economics

We conduct an update of the ranking of economic journals by Kalaitzidakis, Mamuneas and Stengos (2003). However, our present study differs methodologically from that earlier study in an important dimension. We use a rolling window of years between 2003 and 2008, for each year counting the number of citations of articles published in the previous ten years. This allows us to obtain a smoother longer view of the evolution of rankings in the period under consideration and avoid the inherent randomness that may exist at any particular year. Using this framework we proceed to examine the relative ranking of the Canadian Journal of Economics over time. We find the Canadian Journal managed not only to maintain its relative position, but to also improve it over time.

The Contribution of Pollution to Productivity Growth.

In this paper we examine the effect of pollution, as measured by CO2 emissions, on economic growth among a set of OECD countries during the period 1981-1998. We examine the relationship between total factor productivity (TFP) growth and pollution using a semiparametric smooth coefficient model that allow us to directly estimate the output elasticity of pollution. The results indicate that there exists a nonlinear relationship between pollution and TFP growth. The output elasticity of pollution is small with an average sample value of 0.008. In addition we find an average contribution of pollution to productivity growth of about 1 percent for the period 1981-1998. JEL Classifications: C14, O13, O40TFP Growth, Pollution, Semiparametric Estimation.

Social Influence and the Collective Dynamics of Opinion Formation

Social influence is the process by which individuals adapt their opinion, revise their beliefs, or change their behavior as a result of social interactions with other people. In our strongly interconnected society, social influence plays a prominent role in many self-organized phenomena such as herding in cultural markets, the spread of ideas and innovations, and the amplification of fears during epidemics. Yet, the mechanisms of opinion formation remain poorly understood, and existing physics-based models lack systematic empirical validation. Here, we report two controlled experiments showing how participants answering factual questions revise their initial judgments after being exposed to the opinion and confidence level of others. Based on the observation of 59 experimental subjects exposed to peer-opinion for 15 different items, we draw an influence map that describes the strength of peer influence during interactions. A simple process model derived from our observations demonstrates how opinions in a group of interacting people can converge or split over repeated interactions. In particular, we identify two major attractors of opinion: (i) the expert effect, induced by the presence of a highly confident individual in the group, and (ii) the majority effect, caused by the presence of a critical mass of laypeople sharing similar opinions. Additional simulations reveal the existence of a tipping point at which one attractor will dominate over the other, driving collective opinion in a given direction. These findings have implications for understanding the mechanisms of public opinion formation and managing conflicting situations in which self-confident and better informed minorities challenge the views of a large uninformed majority.Comment: Published Nov 05, 2013. Open access at: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.007843

Uniqueness of Petrov type D spatially inhomogeneous irrotational silent models

The consistency of the constraint with the evolution equations for spatially inhomogeneous and irrotational silent (SIIS) models of Petrov type I, demands that the former are preserved along the timelike congruence represented by the velocity of the dust fluid, leading to \emph{new} non-trivial constraints. This fact has been used to conjecture that the resulting models correspond to the spatially homogeneous (SH) models of Bianchi type I, at least for the case where the cosmological constant vanish. By exploiting the full set of the constraint equations as expressed in the 1+3 covariant formalism and using elements from the theory of the spacelike congruences, we provide a direct and simple proof of this conjecture for vacuum and dust fluid models, which shows that the Szekeres family of solutions represents the most general class of SIIS models. The suggested procedure also shows that, the uniqueness of the SIIS of the Petrov type D is not, in general, affected by the presence of a non-zero pressure fluid. Therefore, in order to allow a broader class of Petrov type I solutions apart from the SH models of Bianchi type I, one should consider more general ``silent'' configurations by relaxing the vanishing of the vorticity and the magnetic part of the Weyl tensor but maintaining their ``silence'' properties i.e. the vanishing of the curls of $E_{ab},H_{ab}$ and the pressure $p$.Comment: Latex, 19 pages, no figures;(v2) some clarification remarks and an appendix are added; (v3) minor changes to match published versio

Ranking with social cues: Integrating online review scores and popularity information

Online marketplaces, search engines, and databases employ aggregated social information to rank their content for users. Two ranking heuristics commonly implemented to order the available options are the average review score and item popularity-that is, the number of users who have experienced an item. These rules, although easy to implement, only partly reflect actual user preferences, as people may assign values to both average scores and popularity and trade off between the two. How do people integrate these two pieces of social information when making choices? We present two experiments in which we asked participants to choose 200 times among options drawn directly from two widely used online venues: Amazon and IMDb. The only information presented to participants was the average score and the number of reviews, which served as a proxy for popularity. We found that most people are willing to settle for items with somewhat lower average scores if they are more popular. Yet, our study uncovered substantial diversity of preferences among participants, which indicates a sizable potential for personalizing ranking schemes that rely on social information.Comment: 4 pages, 3 figures, ICWS

Analysis of sports policy in Greece through a strategic relations perspective 1980–93

The aim of this study is to identify the changing nature of sports policy in Greece in the period 1980–93. Key themes addressed were the relationship between policy goals and the political values of the principal political actors; the impact of the changing nature of the economic and social structure on policy goals and implementation; and the significance of national, local and transnational influences and contexts for sports policy. This study reflects a concern to develop knowledge in this field, in the sense both that Greek sports policy as an object of study has received little research attention, and that the framework of strategic relations theory, which has informed this analysis, has not been employed to date in investigations of sports policy systems in the literature. [Continues.

Analysis of sports policy in Greece, through a strategic relations perspective 1980-93

The aim of this study is to identify the changing nature of sports policy in Greece in the period 1980-93. Key themes addressed were the relationship between policy goals and the political values of the principal political actors; the impact of the changing nature of the economic and social structure on policy goals and implementation; and the significance of national, local and transnational influences and contexts for sports policy. This study reflects a concern to develop knowledge in this field, in the sense both that Greek sports policy as an object of study has received little research attention, and that the framework of strategic relations theory, which has informed this analysis, has not been employed to date in investigations of sports policy systems in the literature. Gathering of data in Greece, incorporated both secondary sources, which provided aspects of the structural picture of sport, and primary data derived from interviews, which principally focused on the relations between actual policy outcomes, the goals of individuals and groups, and the struggles occurring within the social and political structure. Interviews were undertaken at various levels within the hierarchies of sports organisation and of the state. The principal elements of the concluding analysis in this study were: first, a focus on political change, from the socialist to right wing government, which resulted in changes in economic and social policy, which were themselves reflected in the nature of sports policy; second, a focus on the position of groups and individuals, and the strategic relations within the structures which are subject to policy changes; and third, an analysis of how local, national, and transnational influences have mediated the context of sports policy in Greece from 1980 to 1993. Having concluded the analysis of empirical data, a number of key themes are developed. These include the significance of the political values of the principal parties on the nature of policy goals at national level; the evidence of clientelistic relations between central government and national governing bodies of sport; patterns of corporatism in the relations between local government and local sporting bodies; and the impact of political partisanship in the relations between central and local government and its implications for sports policy at local government level. The study concludes by reviewing these phenomena within the context of the conceptual framework implied by strategic relations theory