Selection-bias correction based on the multinomial logit: An application to the Mexican labor market

In this presentation, we illustrate an application of a relatively new selection-bias correction methodology based on the multinomial logit model using the selmlog Stata command (Bourguignon, Fournier, and Gurgand, 2007, Journal of Economic Surveys 21: 174–205). selmlog allows for getting both consistent and efficient estimates of the selection process and a fairly good correction for the outcome equation, even when the independence of irrelevant alternatives (IIA) assumption is not achieved. The exercise depicts the current pattern of the occupational choices for the individuals in the Mexican labor market using a longitudinal panel with microdata from the Encuesta Nacional de Ocupación y Empleo (ENOE) during February 2008 to March 2009. We estimate an equation over an endogenously selected population. The command grants simplicity for both distributional and IIA assumptions for parametric models.

Crustal Characteristics in the Subduction Zone of Mexico: Implication of the Tectonostratigraphic Terranes on Slab Tearing

During the past years, significant work has been done for studying the crustal anisotropy and state of stress of the Mexican subduction zone. At the same time, there is new evidence of the geometry of the subducted slab proposing subduction tearing. Here, we present a study of the Earth crust using three different methods: azimuthal anisotropy based on ambient noise, shear‐wave splitting of tectonic tremors, and moment tensor inversions of the earthquakes of 7 September 2017 M_w 8.2 Tehuantepec, Mexico. This earthquake initiated a seismic sequence that triggered shallow seismicity and aftershocks. The shallow earthquakes fall into a region where there were few published focal mechanism higher than M_w 4.5. Two slab tearings: in the Michoacán–Guerrero border and in central Oaxaca, best represent the slab geometry of the Mexican subduction zone. At the Michoacán–Guerrero, the subducted slab is subhorizontal, whereas in central Oaxaca the plate is characterized by northeast vergence. We interpret that the mantle’s flow in this part of the subducted slab produces multiple alignments in the crust and differentiates the tectonostratigraphic terranes of the southern region of Mexico

Servicios Sociales en la Fuerzas Armadas.

Sin resume

Polarización por subgrupos socioeconómicos en México: 1984-2002

Es bien sabido que no existe consenso único en la definición de clase social (i. e. clase baja, media y alta) y que, en el intento por cuantificarlas, se han producido resultados ambiguos y poco confiables. Con este punto de partida, el artículo aplica empíricamente -para el caso de México, período 1984- 2002 la medida generalizada y pionera de la polarización de Esteban et al. (1999) y la de Gradín (2000). Ambas mediciones permiten estratificar a los individuos a través de una reagrupación estadística de la distribución y de sus atributos socioeconómicos, respectivamente, empleando los microdatos de la Encuesta Nacional de Ingresos y Gastos de los Hogares (ENIGH). Una vez que los subgrupos son obtenidos, se recurre a un modelo de probabilidad multivariada del tipo Probit Ordenado, que relaciona la influencia que las variables ejercen hacia los subgrupos, obteniéndose las probabilidades y los efectos marginales respectivos. Los resultados indican que las distancias de los ingresos entre los subgrupos se ampliaron en el período analizado y que el mayor efecto en separar los subgrupos poblacionales lo indujo la variable educativa. El modelo Probit revela que, entre 1984 y 2002, los hogares mexicanos requieren cualidades superiores en el afán de mejorar sus condiciones como grupo social -tal como un mayor nivel educativo-, mostrando a su vez que vivir en zonas urbanas ya no es garantía de pertenencia a la clase media, como solía ser al inicio del mencionado período

Analysis of periodic solutions of the system Janus - Epimetheus

Desenvolupament d'un model 2-dimensional per el sistema coorbital de Janus i Epimetheus al voltant de Saturn, afegint l'aplanament del planeta. Demostracio d'un teorema de simetries sobre les equacions de moviment i analisi numeric del sistema per trobar solucions periodiques/quasi-periodiques utilitzant el teorema de simetries

Olanchito i Sonaguera: memòria d'una cooperació

Abstract not availabl

Comparison of the Tax System Progressivity Over Time: Theory and Application with Mexican Data

Assessing the progressivity of a fiscal system is relevant to develop a global idea on the extent of redistribution. In this paper we assess the evolution of progressivity over time and how economic shocks and government fiscal policy affects its design. The social performance of fiscal redistributive mechanisms in Mexico has been receiving a growing interest from politicians and researchers. The aim of this paper is to assess the dynamics of progressivity of the fiscal system in Mexico and its effect on inequality and on polarization, and this during the period of 2002-2012. What distinguishes this work is the relevance of the adopted comparison approach of progressivity and where the common support of comparison is imposed. The results of this study confirm the effectiveness of the governmental redistributive mechanisms to decrease after-tax income inequality. Based on our estimates, we find a significant increase in the progressivity of the fiscal system over time, despite the high persistent levels of polarization and inequality in the country. Finally, we find that imposing the common support of comparison has a non-negligible impact on the level of progressivity