BUSCADOR RECOLECTA

The cleaning up of waste present in transboundary rivers, which requires the cooperation of different authorities, is a problematic issue, especially when responsibility for the discharge of the waste is not well-defined. Following Ni and Wang (2007) we assume that a river is a segment divided into several regions from upstream to downstream. We show that when the transfer rate of the waste is unknown, the clean-up cost vector provides useful information for estimating some limits in regard to the responsibility of each region. We propose a cost allocation rule, the Upstream Responsibility rule, which takes into account these limits in distributing costs “fairly” and we provide an axiomatic characterization of this rule via certain properties based on basic ideas concerning the responsibility of regions., Jorge Alcalde-Unzu acknowledges the financial support from the Spanish Government through the project ECO2012–34202 and Fundación Ramón Areces. María Gómez-Rúa acknowledges the financial support from the Spanish Government through the project ECO2011-23460 and the Galician Government through the project 2013XGCEDU08072013EMER. Elena Molis acknowledges the financial support from the Spanish Government through the projects ECO2012–31346 and ECO2013–44879–R, from the Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía through the projects SEJ–492 and SEJ–1436 and from the Basque Government through the project IT568–13.

The premature mortality of female children is an alarming demographic outcome in many countries of the world. The most
popular explanation for this phenomenon is the prevalence of son preference. However, empirical findings indicate that the assumption
of a positive relationship between wanted daughters and female children¿s survival is not found in every scenario, and it does not have a
clear explanation in the literature. To fill this gap, we present a simple model that provides insights into how the positive marginal effect
of wanted daughters on their survival might decrease with higher societal discrimination against young females. The model draws on the
emerging literature that examines the erosion of cognitive and noncognitive skills that results from poverty and discrimination. Our theoretical findings are tested for the case of India, using the third round of the National Family Health Survey, with Zero-Inflated Poisson
models. Our estimates provide support for the interaction of parents¿ preferences and societal discrimination against female children. In
particular, we show that the statistical significance of the marginal effect of wanted daughters on their survival disappears in contexts of
high societal discrimination against female children. Our study contributes to the literature by questioning the commonly held assumption of additive separability between the effect of family and societal characteristics. One central implication is that the alleviation of
poverty alone might fail to automatically reduce sex-based discriminatory practices, and that multidimensional interventions are required that target the individual and society, Spanish Government (CICYT: ECO2012-33121, ECO2012-34202)

This paper develops a general model of common resource extraction where we introduce payments for environmental services to encourage resource users to give up extraction. The goal is to reach a balance between resource use and conservation. As the essence of conservation is dynamic, we use a dynamic model to study the implementation of the compensation scheme. A stable heterogeneous equilibrium can be reached where both extractors and non-extractors live together. We analyze how the success of the compensation depends on factors such as the elasticity of demand and the biological characteristics of the resource., Financial support from projects ECO2009-12836 and ECO2012-34202 of the Spanish Minister of Science and Innovation.

This paper is devoted to the study of how to extend a dichotomous
partition of a universal set X into good and bad objects to an ordering
on the power set of X. We introduce a family of rules that naturally
take into account the number of good objects and the number of bad
objects, and provide axiomatic characterizations of two rules that are
particularly appealing when it comes to compating sets in which the
good, R. Arlegi
gratefully acknowledges financial support from the Spanish Ministry of Education,
projects ECO2012-34202 and ECO2015-65031-R.

In this paper we experimentally test Schelling’s (1971) segregation model and confirm the striking result of segregation. In addition, we extend Schelling’s model theoretically by adding strategic behaviour and moving costs. We obtain a unique subgame perfect equilibrium in which rational agents facing moving costs may find it optimal not to move (anticipating other participants’ movements). This equilibrium is far from full segregation. We run experiments for this extended Schelling model, and find that the percentage of full segregated societies notably decreases with the cost of moving and that the degree of segregation depends on the distribution of strategic subjects., Financial support from the Spanish Economy and Competitiveness Ministry (ECO2014-55745-R, ECO2013-46550-R, ECO2013-44879-R, SEJ-2012-1436, ECO2012-34202), Fundación BBVA, Junta de Andalucía Excelencia (P07-SEJ-02547) and Generalitat Valenciana (PROMETEOII/2014/054) is gratefully acknowledged.

This paper explores optimality of contracts and incentives when the principal (public organization) can undertake investments to change agents’ (public workers) identity. In the model, workers within the organization can have different identities. We develop a principal-agent dynamical model with moral hazard, which captures the possibility of affecting this workers’ identity through contracts offered by the firm. In the model, identity is a motivation source which reduces agents’ disutility from effort. We use the term identity to refer to a situation in which the worker shares the organizational objectives and views herself as a part of the organization. Contrary, we use the term conflict to refer to a situation in which workers behave self-interested and frequently in the opposite way of the organisation. We assume that the principal can include investments to foster identity in contracts. Think for instance in developing a single culture that is shared by all the members of an organization. We discuss the conditions under which spending resources in changing workers’ identity and invest in this kind of motivational capital is optimal for organizations. Our results may help to inform public firms’ managers about the optimal design of incentive schemes and policies. For instance, we conclude that investing in motivational capital is the best option in the long run whereas pure monetary incentives works better in the short run., The authors would like to thank the Spanish Ministry of Science and Innovation for financial support of these projects (ECO2009-12836, ECO2012-34202).

This paper analyzes to what extent the definition of property rights affects cropping decisions when these decisions generate negative externalities. To that end, we implement an experimental study where agents make cropping decisions in two different treatments: private and common land. The results show that there are no statistically significant differences between the two treatments in the contribution to the negative externality, thus revealing that the definition of property rights does not affect cropping decision in this context. Furthermore, our findings indicate that the implication of the agents in activities generating negative externalities tends to increase over time, thus amplifying its adverse consequences., Financial support from projects ECO2009-12836, ECO2012-34202 and ECO2011-29314-C02-01.

We study axiomatically situations in which the society agrees to treat voters with different characteristics distinctly. In this setting, we propose a set of intuitive axioms and show that they jointly characterize a new class of voting procedures, called Type-weighted Approval Voting. According to this family, each voter has a strictly positive and finite weight (the weight is necessarily the same for all voters with the same characteristics) and the alternative with the highest number of weighted votes is elected. The implemented voting procedure reduces to Approval Voting in case all voters are identical or the procedure assigns the same weight to all types. Using this idea, we also obtain a new characterization of Approval Voting., The first author’s financial support from the Spanish Ministry of Education and Science, through the project ECO2012–34202, and Fundación Ramón Areces is gratefully acknowledged. The second author’s financial support from the Spanish Ministry of Education and Science, through the project ECO2012–31985, and Fundación Ramón Areces is gratefully acknowledged.

In local social migrations, agents move from their initial location looking for a better local social environment. Social migrations processes do not change the number of social agents of a given type (i.e., the empirical distribution of the population) but their spatial location. Although cellular automata seems to appear as a natural approach to model of social migrations, the evolution of the configuration through a cellular automata might induce a new configuration wherein the number of agents of each type might be actually modified. This article provides a characterization of these cellular automata rules such that for any initial empirical distribution, the evolution of the configuration through a cellular automata of such class induces a new configuration with the same empirical distribution as the initial one, as required to model local social migrations. A class of sequences is defined in order to establish a sufficient condition to maintain this invariance property., Support from projects JC2009-00189 and MC238206 is also gratefully acknowledged. J. M. Benito-Ostolaza acknowledges financial support from Project ECO2009-12836 of the Ministry of Science and Innovation of Spain and Project ECO2012-34202 of Ministry of Economy and Competitivity of Spain. Likewise, P. Hernandez and J. Vila thank the Spanish Ministry of Science and Innovation and the European Feder Funds for financial support under project ECO2010-20584 and ECO2013-46550-R as well as the Prometeo Programme Funds PROMETEO/2009/068 and PROMETEOII/2013/019.