3 resultados para Tempered MCMC
em Dalarna University College Electronic Archive
Chinese Basic Pension Substitution Rate: A Monte Carlo Demonstration of the Individual Account Model
Resumo:
At the end of 2005, the State Council of China passed ”The Decision on adjusting the Individual Account of Basic Pension System”, which adjusted the individual account in the 1997 basic pension system. In this essay, we will analyze the adjustment above, and use Life Annuity Actuarial Theory to establish the basic pension substitution rate model. Monte Carlo simulation is also used to prove the rationality of the model. Some suggestions are put forward associated with the substitution rate according to the current policy.
Resumo:
This thesis presents an adaptive tuning system that can be described as a dynamic Just Intonation tuning system, being compatible with equally tempered instruments. The tuning system is called Hermode Tuning (HMT) and the tuning used as comparison for evaluation is the standardized western tuning, the equal tempered tuning. This study investigates preferences for these two musical tuning systems, depending on whether the tunings are presented on a piano or with woodwind instruments. A listening test was done with students at the Falun Conservatory of Music, including both a vertical listening (intervalls) and a horizontal listening (cadenses and musical compositions) of Hermode tuned musical material. Overall the results showed no significant preferences for either tuning system irrespectively of what instrument it was presented with. The clearest results was that of a misjudged just intonated perfect third on the piano and a preference for an adaptively tuned piano presented in a simple harmonic structure, with a parameter setting of HMT 70%. Materials for comparison was partly taken from Hermode´s own website, but overall the attitude towards these sequenses (using a likert scale of one to five) showed a low expected value. This shows the complexity of the topic and no general conclusions regarding the choice of intonation or tuning system could be done for the presented material.
Resumo:
Background: The sensitivity to microenvironmental changes varies among animals and may be under genetic control. It is essential to take this element into account when aiming at breeding robust farm animals. Here, linear mixed models with genetic effects in the residual variance part of the model can be used. Such models have previously been fitted using EM and MCMC algorithms. Results: We propose the use of double hierarchical generalized linear models (DHGLM), where the squared residuals are assumed to be gamma distributed and the residual variance is fitted using a generalized linear model. The algorithm iterates between two sets of mixed model equations, one on the level of observations and one on the level of variances. The method was validated using simulations and also by re-analyzing a data set on pig litter size that was previously analyzed using a Bayesian approach. The pig litter size data contained 10,060 records from 4,149 sows. The DHGLM was implemented using the ASReml software and the algorithm converged within three minutes on a Linux server. The estimates were similar to those previously obtained using Bayesian methodology, especially the variance components in the residual variance part of the model. Conclusions: We have shown that variance components in the residual variance part of a linear mixed model can be estimated using a DHGLM approach. The method enables analyses of animal models with large numbers of observations. An important future development of the DHGLM methodology is to include the genetic correlation between the random effects in the mean and residual variance parts of the model as a parameter of the DHGLM.