Thematic Clubs and the Supremacy of Network Externalities

We explore the issue of minorities' survival in the presence of positive network externalities. We rely on a simple example of thematic clubs to illustrate why and how such survival problems might appear, first considering the case of simple‐network effects (fully anonymous externalities) and then the case of cross‐network effects (type‐dependent externalities). In both cases, the analysis is framed as a simple noncooperative game with a continuum of players and binary action sets. There is a unique and interior Nash equilibrium under mild network effects and two corner equilibria under strong network effects, with one club driven out. A utilitarian planner would accentuate the clustering effects of network externalities, and call for the disappearance of the minority club more often than the noncooperative solution. A simple myopic learning algorithm capturing the progression of network lock‐in effects is studied.     

Passports for sale: The political economy of conflict and cooperation in a meta-club

Some of the member states of the European Union sell citizenship or residence to wealthy foreign investors. We analyze these “golden-passport” programs as a study in the political economy of conflict and cooperation in an international meta-club. Seen through the lens of club goods theory, the EU is a club of nations, each of which can be interpreted as itself a club. Each single nation reserves the right to govern the admission of new individual members into its own club, and new members automatically benefit from the EU wide meta-club good. We characterize the unique equilibrium when individual clubs that may differ in membership size are free to choose the terms on which they admit members, and evaluate it from the point of view of the wellbeing of the set of clubs as a whole. We identify club size and benefits as well as differences in cost externalities as the key determinants. We also consider how the set of clubs as a whole can respond to the economic inefficiency problems such a situation creates.     

Value-maximizing football clubs

In this paper, football clubs are modeled as value-maximizing enterprises. With a long-term perspective in this framework, players are not only factors of production, but also assets of the club. It is shown that talent investment is higher with value-maximization than with profit maximization for homogeneous football clubs. Club heterogeneity is then modeled by different time-horizons regarding future profits, which leads to asymmetric levels of talent investment. Teams with longer time-horizons demand more talent and tilt the competition to their favor. Increases in transfer prices for players worsen the competitive balance, while higher player wages improve it.     

Football players’ career and wage profiles

The objective of this article is to look over football players’ career path, from lower leagues to the first league, and the associated wage profile. The information comes from a Portuguese longitudinal matched employer–employee data set defining several career events according to players’ movement across football clubs and across professional and semi-professional leagues. Our identifying strategy relies on coach changes to reduce the potential bias resulting from players’ moves between clubs. The estimated first-difference wage equations indicate that players can expect a wage premium when they get transferred to new clubs in higher leagues or a wage penalty when moving to lower leagues. Players who stay in the same club after the club being relegated can also expect a wage penalty.     

Nonstationarity and Stochastic Stability of Relative Income Clubs

The recent literature on “convergence” of cross‐country per capita incomes has been dominated by the two hypotheses of “global convergence” and “club‐convergence,” pertaining to limits of estimated income distribution dynamics. Utilizing a new measure of “stochastic stability,” we establish two stylized facts regarding short‐ and medium‐term distribution dynamics. The first is non‐stationarity of transition dynamics, in the sense of changing transition kernels, and the second is emergence, disappearance, and re‐emergence of a “stochastically stable” middle income group. This middle income group emerges as the gap between rich and poor clubs gets larger, and it changes the dynamics of transition to and from the rich and poor clubs, eventually narrowing the gap between the poor and rich as the middle club vanishes. Analyzing the stochastic stability of middle‐income groups is thus a first step toward understanding higher‐order dynamics of narrowing or widening of the gap between rich and poor countries.     

Flexible Integration? Mandatory and Minimum Participation Rules

For a club such as the European Union, an important question is whether a subset of the members should be allowed to form “inner clubs” and enhance cooperation. Flexible cooperation allows members to participate if and only if they benefit, but it leads to free‐riding when externalities are positive. I show that flexible cooperation is better if the heterogeneity is large and the externality small, but that rigid cooperation is the political equilibrium too often. Both regimes, however, are extreme variants of a more general system combining mandatory and minimum participation rules. For each rule, I characterize the optimum and the equilibrium.     

Private good clubs and the core

The incentive for potential club members to form private good clubs is an average cost function that is decreasing over at least part of its range. Benefits to club members are measured by consumer's surplus, and a game theoretic characteristic function is used to describe total club benefits. Then, in the game framework, the optimum club size is examined and related to the existence of the core, which in turn is shown to be crucially dependent on the demand and cost curves.     

Farsighted network formation

This paper studies a model of dynamic network formation when individuals are farsighted: players evaluate the desirability of a “current” move in terms of its consequences on the entire discounted stream of payoffs. We define a concept of equilibrium which takes into account farsighted behavior of agents and allows for limited cooperation amongst agents. We show that an equilibrium process of network formation exists. We also show that there are valuation structures in which no equilibrium strategy profile can sustain efficient networks. We then provide sufficient conditions under which the equilibrium process will yield efficient outcomes.     

Sophisticated Experience-Weighted Attraction Learning and Strategic Teaching in Repeated Games

Most learning models assume players are adaptive (i.e., they respond only to their own previous experience and ignore others' payoff information) and behavior is not sensitive to the way in which players are matched. Empirical evidence suggests otherwise. In this paper, we extend our adaptive experience-weighted attraction (EWA) learning model to capture sophisticated learning and strategic teaching in repeated games. The generalized model assumes there is a mixture of adaptive learners and sophisticated players. An adaptive learner adjusts his behavior the EWA way. A sophisticated player rationally best-responds to her forecasts of all other behaviors. A sophisticated player can be either myopic or farsighted. A farsighted player develops multiple-period rather than single-period forecasts of others' behaviors and chooses to “teach” the other players by choosing a strategy scenario that gives her the highest discounted net present value. We estimate the model using data from p-beauty contests and repeated trust games with incomplete information. The generalized model is better than the adaptive EWA model in describing and predicting behavior. Including teaching also allows an empirical learning-based approach to reputation formation which predicts better than a quantal-response extension of the standard type-based approach. Journal of Economic Literature Classification Numbers: C72, C91.     

A Theoretical Analysis of the Influence of Money Injections on Risk Taking in Football Clubs

This paper analyzes the adverse incentive effects produced by money injections of benefactors [sugar daddies (SD)]. We show that the existence of a SD induces the club to choose a riskier investment strategy and the more the SD commits to bailout the club, the more the clubs’ optimal level of riskiness increases. Moreover, a private SD bails out the club less often than a public SD. Our model further shows that a ‘too‐big‐to‐fail’ phenomenon exists because it is optimal to always bailout a club if its market size is sufficiently large.     

Consumer mobility and community tax bases : The financing of local public goods

In a model of economic ‘clubs’, size is fixed and members consuming a public good raise the question of composition; with whom would they rather consume? This depends on the way collective consumption is financed, and three results are proven With a poll tax, clubs must be homogeneous in income for all to be satisfied With a marginal benefit (Lindahl) tax, no consumer is ever satisfied with any composition; and with an income tax, at least one consumer in each club is always dissatisfied. Satisfaction implies there exists no club composition preferred to the existing one.     

Farsightedly stable networks

A set of networks G is pairwise farsightedly stable (i) if all possible farsighted pairwise deviations from any network g∈ G to a network outside G are deterred by the threat of ending worse off or equally well off, (ii) if there exists a farsighted improving path from any network outside the set leading to some network in the set, and (iii) if there is no proper subset of G satisfying conditions (i) and (ii). A non-empty pairwise farsightedly stable set always exists. We provide a full characterization of unique pairwise farsightedly stable sets of networks. Contrary to other pairwise concepts, pairwise farsighted stability yields a Pareto dominant network, if it exists, as the unique outcome. Finally, we study the relationship between pairwise farsighted stability and other concepts such as the largest pairwise consistent set and the von Neumann–Morgenstern pairwise farsightedly stable set.     

Drugs,guns, and targeted competition

We consider a dynamic competition game involving three players, in which each player can vary the extent of his competition on a per-rival basis. We call such competition targeted. We show that if the players are myopic, then the weaker players eventually lose the game to their strongest rival. If instead the players are sufficiently far-sighted, then all three players converge in their power and stay in the game. We develop our model in application to drug wars, but the approach of targeted competition can be applied to competition between firms or political parties, or to warfare.     

Farsightedly stable networks

A set of networks G is pairwise farsightedly stable (i) if all possible farsighted pairwise deviations from any network g G to a network outside G are deterred by the threat of ending worse off or equally well off, (ii) if there exists a farsighted improving path from any network outside the set leading to some network in the set, and (iii) if there is no proper subset of G satisfying conditions (i) and (ii). A non-empty pairwise farsightedly stable set always exists. We provide a full characterization of unique pairwise farsightedly stable sets of networks. Contrary to other pairwise concepts, pairwise farsighted stability yields a Pareto dominant network, if it exists, as the unique outcome. Finally, we study the relationship between pairwise farsighted stability and other concepts such as the largest pairwise consistent set and the von Neumann–Morgenstern pairwise farsightedly stable set.     

Approximate cores of games and economies with clubs

We introduce the framework of parameterized collections of games with and without sidepayments and provide three nonemptiness of approximate core theorems. The parameters bound (a) the number of approximate types of players and the size of the approximation and (b) the size of nearly effective groups of players and their distance from exact effectiveness. Our theorems are based on a new notion of partition-balanced profiles and approximately partition-balanced profiles. The results are applied to a new model of an economy with clubs. In contrast to the extant literature, our approach allows both widespread externalities and uniform results. A fundamental new mathematical result, the partition-balancing effect of large numbers, which promises to have further applications, is contained in Appendix A.     

Structural holes in social networks

We consider a setting where every pair of players that undertake a transaction (e.g. exchange goods or information) creates a unit surplus. A transaction can take place only if the players involved have a connection. If the connection is direct the two players split the surplus equally, while if it is indirect then intermediate players also get an equal share of the surplus. Thus, individuals form links with others to create surplus, to gain intermediation rents, and to circumvent others who are trying to become intermediary.Our analysis clarifies the interplay between these forces in the process of strategic network formation. First, we show that, in the absence of capacity constraints on links, it leads to the emergence of a star network where a single agent acts as an intermediary for all transactions and enjoys significantly higher payoffs. Second, we study the implications of capacity constraints in the ability of agents to form links. In this case, distances between players must be long, which induces players who are “far off” to connect in order to avoid paying large intermediation rents. A cycle network then emerges, payoffs being equal across all players.     

The Gain from International Trade in Pool Goods and Private Goods

It is well known that perfectly competitive free trade is potentially beneficial for all countries if all goods are both rivalrous and excludable in consumption (“private goods”) and recently (2011) the proposition has been modified to accommodate non‐rivalrous and non‐excludable goods (“public goods”), as well as non‐rivalrous and excludable goods (“club goods”). In the present paper the proposition is modified again, to accommodate rivalrous and non‐excludable goods (“pool goods”). The primary focus is on ocean fisheries, access to which is shared (not necessarily equally) by all countries. However the central proposition to be established is valid for all international pool goods.     

Real convergence in Europe: A cluster analysis

In this paper we analyse real convergence in GDP per worker in the EU member states. The aim is to test whether there is evidence of club convergence in the EU, i.e. divergence in GDP per worker. Evidence in favour of cluster or club convergence may be an indication of significant productivity divergences between countries, which may also explain the current turmoil in the euro zone. The results show evidence of different economic growth rates within Europe, which also converge to different steady states, implying divergence in the EU-14. Within the EU-14 member states we observe two convergence clubs, which are not related to the fact that some countries belong to the euro area. Furthermore, Eastern European countries are also divided in two clubs, with a more direct effect of belonging to the euro zone in the composition of the clubs.     

“一带一路”沿线国家贸易网络结构特征及其对技术进步的影响——基于社会网络分析法的研究*

本文采用社会网络分析法探讨了2008—2018年“一带一路”沿线国家贸易网络结构特征,测算沿线国家贸易网络中心位置对技术进步的影响,并对不同收入国家进行异质性分析。研究发现：“一带一路”沿线国家整体贸易结构比较松散,意大利、土耳其、韩国、俄罗斯、中国和新加坡等国家（地区）位于网络核心,共有23个国家（地区）发挥“中介”或“桥梁”作用,影响着其余沿线国家之间的贸易联系;超过四成的沿线国家（地区）与非贸易伙伴国具有较强的间接贸易关系。贸易网络中心位置的提升能显著促进母国技术进步,间接贸易影响母国技术进步的边际效应大于直接贸易;中高等收入水平国家直接和间接贸易地位和贸易强度的提升均显著促进了技术进步,低等收入国家贸易强度的提升也能促进母国的技术进步。     

Inequality and club formation

We study the relationship between social segmentation and income inequality by means of the economic theory of clubs with private provision of the club good. After having characterized the core partition of society in clubs and investigating its characteristics, we show how the clubs’ sizes depend on income distribution and compare segmentation profiles arising in societies characterized by different inequality patterns.