En los estudios de los tiempos de sobrevivencia, además del problema de censuramiento de dichos tiempos, un problema que puede surgir es comparar dos poblaciones X y Y con distribuciones Fx,Fy respectivamente. Esto puede ser el caso de comparar el tiempo de sobrevivencia de pacientes con dos tipos de tratamiento, por ejemplo, uno nuevo y el vigente (tratamiento vs. Control), grupos raciales, etc. En el presente trabajo, estudiaremos las pruebas no paramétricas para el caso de dos muestras, como son la de Wicoxon, de Gehan y de Mantel-Haenszel.

En los estudios de los tiempos de sobrevivencia, además del problema de censuramiento de dichos tiempos, un problema que puede surgir es comparar dos poblaciones X y Y con distribuciones Fx,Fy respectivamente. Esto puede ser el caso de comparar el tiempo de sobrevivencia de pacientes con dos tipos de tratamiento, por ejemplo, uno nuevo y el vigente (tratamiento vs. Control), grupos raciales, etc. En el presente trabajo, estudiaremos las pruebas no paramétricas para el caso de dos muestras, como son la de Wicoxon, de Gehan y de Mantel-Haenszel.

This research aims to show the application of the bootstrap method in the process of estimating the willingness to pay (WTP) for a determined environmental service, using the binary choice model for contingent valuation. The main contribution of the research, is the inclusion of an additional criterion in the bootstrap process, in which samples are randomly selected containing balanced values in the dependent dichotomous variable. For illustrative purposes, it is used the data base from the Postigo (2011) study, in order to estimate the mean, standard error and the confidence interval of the WTP through de bootstrap method. In comparison of the results obtained in the baseline scenario, if the bootstrap method with balanced subsamples is applied, it would be obtained logit coefficients with greater statistical significance and also lower mean and standard error of the WTP.

This research presents a theoretical review of the structure and applica-tion of long memory nature models that combine characteristics of the fractionally integrated processes with the classic GARCH models, thus obtaining the autoregres-sive models with fractionally integrated conditioned heterocedasticity (FIGARCH) which Through the cumulative response impulse function, I can quantify the degree of persistence of the impact of innovation on the function of conditioned variance, that is, the element of persistence in a chaotic series very sensitive to changes in initial conditions associated with fractional Brownian motion. For this application, the exchange rate variable was used, and by means of long memory time series mo-dels, the persistence of the existing effect on the volatility of said series could be analyzed.

In this work, the modeling of the volatility of financial assets is studied using a Bayesian approach. DCC - GARCH models are used, for the errors of these models asymmetric and leptokurtic probability distributions are considered, which are parameterized according to the asymmetry and the weight of the tails, therefore these parameters are also estimated. The estimation of the model parameters was performed using the MCMC methodology Metropolis - Hastings random walk algorithm using the software R package bayesDccGarch, daily data from 04/01/2015 - 01/31/2020 of the stock indices of: Frankfurt are considered (DAX), Tokyo (NIKKEI225), Paris (CAC40), and Lima (BVL). The Bayesian approach to estimating the model parameters facilitates interpretation and provides the ability to insert a priori information for the parameters.

La presente investigación tiene como objetivo mostrar la aplicación del método bootstrap dentro del proceso de estimación de la disposición a pagar (DAP) de un determinado bien y/o servicio ambiental, bajo el enfoque de la valoración contingente de formato binario. El principal aporte de la investigación, es la inclusión de un criterio adicional en el proceso de remuestreo bootstrap, seleccionándose aleatoriamente muestras que contengan valores balanceados en la variable dependiente binaria. Con fines ilustrativos, se utilizó la base de datos del estudio de Postigo (2011), con el objetivo de estimar la media, el error estándar y el intervalo de confianza de la DAP mediante bootstrap. En comparación con los resultados obtenidos usando un remuestreo convencional, al aplicarse el bootstrap con muestras balanceadas, se obtuvo una disminución del promedio y error estándar estima...

This research presents a theoretical review of the structure and applica-tion of long memory nature models that combine characteristics of the fractionally integrated processes with the classic GARCH models, thus obtaining the autoregres-sive models with fractionally integrated conditioned heterocedasticity (FIGARCH) which Through the cumulative response impulse function, I can quantify the degree of persistence of the impact of innovation on the function of conditioned variance, that is, the element of persistence in a chaotic series very sensitive to changes in initial conditions associated with fractional Brownian motion. For this application, the exchange rate variable was used, and by means of long memory time series mo-dels, the persistence of the existing effect on the volatility of said series could be analyzed.