Welfare Implications of the Interaction between Habits and Consumption Externalities

We analyze the welfare properties of the equilibrium path of a growth model where both habits and consumption externalities affect the utility of consumers. Our analysis highlights the crucial role played by complementarities between externalities and habits in order to generate an inefficient dynamic equilibrium. In particular, we show that the competitive equilibrium is inefficient when consumption externalities and habit adjusted consumption are not perfect substitutes.Habit formation, consumption externalities

Aspirations, Habit Formation, and Bequest Motive

We analyze how the presence of endogenous preferences affects the altruistic bequest motive from parents to children. We will show that the existence of habits raises the threshold value of the intergenerational discount factor above which altruistic bequests are positive, while aspiration formation could push this value down. Therefore, the dynamic inefficiency of the economy with no altruism is not sufficient to prevent the bequest motive from being operative under aspiration formation. We also discuss the implications of public debt when the bequest motive is inoperative and preferences exhibit habit and aspiration formation.Aspirations, Habits, Bequests

Estate Taxes, Consumption Externalities, and Altruism

We study how the introduction of consumption externalities affects the efficiency of the dynamic equilibrium in an economy displaying dynastic altruism. When the bequest motive is inoperative consumption externalities affect the intertemporal margin between young and old consumption and thus modify the intertemporal path of consumption and capital. The optimal tax policy that solves this intertemporal inefficiency consists of a tax on capital income and a pay-as-you-go social security system. The later solves the overaccumulation of capital due to the inoperativeness of the bequest motive and the former solves the inefficient allocation of consumption due to consumption externalities. When the bequest motive is operative consumption externalities only cause an intratemporal inefficiency that affects the allocation of consumption between the generations living in the same period but do not affect the optimality of the capital stock level. This suboptimal allocation of consumption implies in turn that the path of bequest is also suboptimal. The optimal tax policy in this case consists of an estate tax and a capital income tax. The estate tax corrects the intratemporal inefficiency but generates an intertemporal inefficiency which is corrected by means of an appropriate capital income tax.Consumption externalities, bequests, optimal tax rates

Can consumption spillovers be a source of equilibrium indeterminacy?

In this paper, we show that consumption externalities are a source of equilibrium indeterminacy in a growth model with endogenous labor supply. In particular, when the marginal rate of substitution between own consumption and the others' consumption is constant along the equilibrium path, the equilibrium does not exhibit indeterminacy. In contrast, when that marginal rate of substitution is not constant, the equilibrium may exhibit indeterminacy even if the elasticity of the labor demand is smaller than the elasticity of the Frisch labor supply.Consumption externalities, equilibrium efficiency, indeterminacy

Consumption Externalities, Habit Formation, and Equilibrium Efficiency

We analyze the welfare properties of the competitive equilibrium in a capital accumulation model where individual preferences are subjected to both habit formation and consumption spillovers. We also discuss how consumption externalities and habits interact to generate an inefficient dynamic equilibrium. Finally, we characterize optimal tax policies aimed to restore efficient decentralized paths.Habit Formation, Consumption Externalities, Equilibrium Efficiency

Sectoral composition and macroeconomic dynamics

We analyze the transitional dynamics of a model with heterogeneous consumption goods. In this model, convergence is driven by two different forces: the typical diminishing returns to capital and the sectoral change inducing the variation in relative prices. We show that this second force affects the growth rate if the two consumption goods are not Edgeworth independent and if these two goods are pro- duced with technologies exhibiting different capital intensities. Because the afore- mentioned dynamic sectoral change arises only under heterogeneous consumption goods, the transitional dynamics of this model exhibits striking differences with the growth model with a single consumption good. We also show that these differences in the transitional dynamics can give raise to large discrepancies in the welfare cost of shocks between the economy with a unique consumption good and the economy with multiple consumption goods.multi-sector growth models, transitional dynamics, consumption growth.

Tecnologia i sostenibilitat. L'experiència de 7 anys d'una assignatura d'introducció a la sostenibilitat a la UPC

Presentació sobre la realització de l'assignatura ALE “Medi ambient i tecnologia. Educació ambiental a l’enginyeria”, dissenyada per la Càtedra Unesco de Sostenibilitat de la UPC. Actualment aquesta assignatura es denomina “Tecnologia i Sostenibilitat”.Peer Reviewe

La construction du sens autour de la notion de compétence dans des dispositifs universitaires en alternance

Lorsque l’on se propose d’étudier le développement de compétences dans des formations de l’enseignement supérieur, il nous semble important d’analyser les « éléments de preuve » que les étudiants peuvent apporter pour démontrer leur acquisition. Les productions en contexte professionnel et en situation scolaire peuvent servir de bases d’évaluation et orienter la démarche d’accompagnement des formateurs. Dans cette recherche, nous allons nous intéresser aux preuves de l’acquisition de compétences chez des étudiants de premier cycle universitaire en éducation sociale, travail social, éducation préscolaire et primaire d’une université espagnole lors de leur stage pratique. Le but est de proposer un modèle d’interprétation de la construction de compétences transversales dans les formations universitaires.When asked to study skill development in higher education training, it seemed important to analyse the “evidence” that students could produce to demonstrate skill acquisition. Productions in the professional and academic context may be used as evaluation criteria and help orient the teacher-training process. In this study, we will be looking at proofs of skill acquisition among first cycle Spanish university students in social education, social work, and preschool and primary education during their practicums. The goal is to create an interpretation model for transversal skill building in teacher-training programs.Al proponernos estudiar el desarrollo de competencias en las formaciones en educación superior, nos pareció importante analizar los « elementos de prueba » que los estudiantes pueden aportar para demostrar sus adquisición. Las producciones en contexto profesional y en situación académica pueden servir de base a la evaluación y orientar el enfoque del acompañamiento de los formadores. En esta investigación nos interesaremos a las pruebas de la adquisición de competencias de los estudiantes de primer ciclo universitario en educación social, trabajo social, educación preescolar y primaria, de una universidad española durante el período de prácticas. El objetivo es proponer un modelo de interpretación de la construcción de competencias transversales en las formaciones universitarias

Radial velocities and metallicities from infrared Ca II triplet spectroscopy of open clusters II. Berkeley 23, King 1, NGC 559, NGC 6603 and NGC 7245

Context: Open clusters are key to studying the formation and evolution of the Galactic disc. However, there is a deficiency of radial velocity and chemical abundance determinations for open clusters in the literature. Aims: We intend to increase the number of determinations of radial velocities and metallicities from spectroscopy for open clusters. Methods: We acquired medium-resolution spectra (R~8000) in the infrared region Ca II triplet lines (~8500 AA) for several stars in five open clusters with the long-slit IDS spectrograph on the 2.5~m Isaac Newton Telescope (Roque de los Muchachos Observatory, Spain). Radial velocities were obtained by cross-correlation fitting techniques. The relationships available in the literature between the strength of infrared Ca II lines and metallicity were also used to derive the metallicity for each cluster. Results: We obtain = 48.6+/-3.4, -58.4+/-6.8, 26.0+/-4.3 and -65.3+/-3.2 km s-1 for Berkeley 23, NGC 559, NGC 6603 and NGC 7245, respectively. We found [Fe/H] =-0.25+/-0.14 and -0.15+/-0.18 for NGC 559 and NGC 7245, respectively. Berkeley 23 has a low metallicity, [Fe/H] =-0.42+/-0.13, similar to other open clusters in the outskirts of the Galactic disc. In contrast, we derived a high metallicity ([Fe/H] =+0.43+/-0.15) for NGC 6603, which places this system among the most metal rich known open clusters. To our knowledge, this is the first determination of radial velocities and metallicities from spectroscopy for these clusters, except NGC 6603, for which radial velocities had been previously determined. We have also analysed ten stars in the line of sight to King 1. Because of the large dispersion obtained in both radial velocity and metallicity, we cannot be sure that we have sampled true cluster members.Comment: 10 pages, 5 figures, accepted for publication in A&A (minor modifications