The Solow model in discrete time and decreasing population growth rate

This paper reformulates the neoclassical Solow-Swan model of economic growth in discrete time by introducing a generic population growth law that verifies the following properties: 1) population is strictly increasing and bounded 2) the rate of growth of population is decreasing to zero as time tends to infinity. We show that in the long run the capital per worker of the model converges to the non-trivial steady state of the Solow Swan model with zero labor growth rate. In addition we prove that the solutions of the model are asymptotically stable.Solow model

THE EFFECTS ON ENVIRONMENTAL INVESTMENT OF CHANGES IN TOURISM DEMAND

In this short paper we analyze the impact of tourist demand in hotel rooms on the investment of hotels on environmental quality. We show that when income of the tourists increases, then to maintain the demand for rooms, the hotels must in-crease the investment on the environmental quality of the region where there is an increment of the tourist activity. In the particular case where we have three differ-ent hotel chains located in three different tourist regions, we show that the incen-tive of hotel chains to invest in environmental quality depends on the demand for days of rest on the part of tourists and on the level of aggregate income. We also show that if total income increase, then the incentive to invest in environmental quality increases in the region where the price of a hotel room is lower.environmental investment, hotelling competition, service quality, sustainable tourism

Learning strategies in modelling economic growth

Cornerstone economic growth models as the Solow-Swan model and their modern extensions normally assume the rate of population growth as exogenous without any explanation of the links between economic growth and most important demographic variables. Recently, some articles have presented models to explain many phenomena of population dynamics, including evolution and ageing. This paper is a first exercise to include endogenous population dynamics and learning strategies as ingredients of an economic growth model. The model includes two ways of learning that determinate economic growth: individual and social learning. We study the dynamics through computer simulations and we show that the model reflects some features of real economies.Economic Growth, Learning Strategies, Human Capital, Penna model

Strategic complementarities and unraveling in matching markets

We present a theoretical explanation of inefficient early matching in matching markets. Our explanation is based on strategic complementarities and strategic unraveling. We identify a negative externality imposed on the rest of the market by agents who make early offers. As a consequence, an agent may make an early offer because she is concerned that others are making early offers. Yet other agents make early offers because they are concerned that others worry about early offers, and so on and so forth. The end result is that any given agent is more likely to make an early offer than a late offer

Strategic Uncertainty and Unraveling in Matching Markets

We present a theoretical explanation of inefficient early matching in matching markets. Our explanation is based on strategic uncertainty and strategic unraveling. We identify a negative externality imposed on the rest of the market by agents who make early offers. As a consequence, an agent may make an early offer because she is concerned that others are making early offers. Yet other agents make early offers because they are concerned that others worry about early offers; and so on and so forth. The end result is that any given agent is more likely to make an early offer than a later offer

Egg clutch structure of Rhinella rumbolli (Anura: Bufonidae), a toad from the Yungas of Argentina, with a review of the reproductive diversity in Rhinella

Rhinella rumbolli is a poorly known, medium-sized toad endemic to the Yungas of Argentina. Recent fieldwork allowed observing its peculiar oviposition mode, which is described in this paper. A review of literature and examination of museum material indicate that oviposition in Rhinella can vary from strings of eggs in a gelatinous tube (uniserial, biserial or multiserial) to open clumps. Clutch features in Rhinella provide informative variation for taxonomic and phylogenetic studies and help to understand the relationships in this large genus of true toads.Fil: Pereyra, Martín Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Vera Candioti, María Florencia. Fundación Miguel Lillo. Dirección de Zoología. Instituto de Herpetología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Faivovich, Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Baldo, Juan Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; Argentin

Respecting priorities versus respecting preferences in school choice: When is there a trade-off?

A classic trade-off that school districts face when deciding which matching algorithm to use is that it is not possible to always respect both priorities and preferences. The student-proposing deferred acceptance algorithm (DA) respects priorities but can lead to inefficient allocations. We identify a new condition on school choice markets under which DA is efficient. Our condition generalizes earlier conditions by placing restrictions on how preferences and priorities relate to one another only on the parts that are relevant for the assignment. Whenever there is a unique allocation that respects priorities, our condition captures all the environments for which DA is efficient. We show through stylized examples and simulations that our condition significantly expands the range of known environments for which DA is efficient. We also discuss how our condition sheds light on existing empirical findings

Las tasas de mortalidad para la Enfermedad de Parkinson están incrementando en Espana. ˜ Un análisis Edad-Periodo-Cohorte y Joinpoints en las tasas de mortalidad desde 1981 a 2020

Background: Mortality in Parkinson’s disease is increasing worldwide, but Spanish data need further study. Objective: To analyse the mortality trends of Parkinson’s disease in Spain between 1981 and 2020. Methods: This observational retrospective study assessed the Parkinson’s disease mortality data from 1981 to 2020 collected from the National Statistics Institute of Spain. Agestandardised mortality rates were analysed by age and sex groups, detecting significant mortality trends through a joinpoint analysis. Age-period-cohort effect and potential years of life lost analyses were conducted. The European standard population of 2013 was considered for the analyses. Results: A total of 88 034 deaths were assessed. The overall age-standardised mortality rate rose throughout the period from 3.67 to 8.57 per 100 000 inhabitants. Mortality rates in men were higher than in women, 11.63 versus 6.57 deaths per 100 000 inhabitants. The sex ratio showed an increase in premature mortality in men during 2020. The overall joinpoint analysis recorded a rise in mortality, primarily since the 20th century, mainly in male and older groups, that matched with a period effect. The age effect was detected, confirming higher mortality at an older age. The analysis of potential years of life lost detected a growth in this rate, changing from 0.66 in 1981 to 1.06 in 2020. Conclusions: Mortality data for Parkinson’s disease in Spain rose significantly in forty years. Mortality rate was higher in the male and age group above 75 years of age. The sex ratio showed premature mortality in men in 2020, which will need further study.Introducción: La mortalidad de la Enfermedad de Parkinson está incrementando a nivel mundial, pero los datos espanoles ˜ necesitan ser estudiados en profundidad. Objetivo: Analizar las tendencias de mortalidad de la Enfermedad de Parkinson en Espana˜ entre 1981 y 2020. Métodos: Este estudio observacional retrospectivo analizó los datos de mortalidad de la Enfermedad de Parkinson extraídos desde 1981 a 2020 del Instituto Nacional de Estadística de Espana. ˜ Las tasas de mortalidad estandarizada por edad fueron analizadas por grupos de edad y sexo, detectando cambios de tendencia de mortalidad significativos mediate un análisis de joinpoint. Se llevaron a cabo análisis de Edad-Periodo-Cohorte y anos ˜ potenciales de vida perdidos. La población estándar europea fue considerada para el análisis. Resultados: Un total de 88.034 defunciones fueron examinadas. La tasa global de mortalidad estandarizada por edad creció a lo largo del periodo estudiado desde 3,67 a 8,47 por cada 100.000 habitantes. Las tasas de mortalidad fueron mayores en hombre que en mujeres, 11,63 frente a 6,57 fallecimientos por cada 100.000 habitantes. La proporción de sexo mostró un incremento en la mortalidad prematura en hombre durante 2020. El análisis de joinpoint global reportó un aumento de mortalidad, principalmente desde el siglo XX, siendo más notable en hombre y grupos de edad avanzada, que coincidió con un efecto periodo. Se detectó un efecto de edad confirmando una mayor mortalidad a edad más edad avanza. El análisis de anos ˜ potenciales de vida perdidos detectó un crecimiento en esta tasa, cambiando de un 0,66 en 1981 a 1,06 en 2020. Conclusiones: Los datos de mortalidad para la Enfermedad de Parkinson en Espana˜ ha incrementado significativamente durante cuarenta anos. ˜ La tasa de mortalidad fue mayor en hombre y en grupos de edad mayores de 75 anos ˜ de edad. La proporción de sexo mostró una mortalidad prematura en hombres en 2020, que necesitará ser estudiado en mayor profundidad