Bayesian parameter inference for partially observed stopped processes

We consider Bayesian parameter inference associated to partially-observed stochastic processes that start from a set B ₀ and are stopped or killed at the first hitting time of a known set A. Such processes occur naturally within the context of a wide variety of applications. The associated posterior distributions are highly complex and posterior parameter inference requires the use of advanced Markov chain Monte Carlo (MCMC) techniques. Our approach uses a recently introduced simulation methodology, particle Markov chain Monte Carlo (PMCMC) (Andrieu et al. 2010), where sequential Monte Carlo (SMC) (Doucet et al. 2001; Liu 2001) approximations are embedded within MCMC. However, when the parameter of interest is fixed, standard SMC algorithms are not always appropriate for many stopped processes. In Chen et al. (2005), Del Moral (2004), the authors introduce SMC approximations of multi-level Feynman-Kac formulae, which can lead to more efficient algorithms. This is achieved by devising a sequence of sets from B ₀ to A and then performing the resampling step only when the samples of the process reach intermediate sets in the sequence. The choice of the intermediate sets is critical to the performance of such a scheme. In this paper, we demonstrate that multi-level SMC algorithms can be used as a proposal in PMCMC. In addition, we introduce a flexible strategy that adapts the sets for different parameter proposals. Our methodology is illustrated on the coalescent model with migration.     

Burnout in Greek teachers: Main findings and validity of the Maslach Burnout Inventory

The factorial structure of the Maslach Burnout Inventory (Maslach and Jackson 1986) was investigated in a sample of 220 Greek teachers and was found to be similar to that reported by Maslach and Jackson. A job satisfaction measure was employed for the investigation of the discriminant validity of the burnout measure. Correlations between job satisfaction and the three burnout dimensions were found to be low to moderate. It is suggested that the relationship and the degree of overlap between emotional exhaustion and job satisfaction require further examination. Greek teachers reported lower levels of burnout on the emotional exhaustion and depersonalization scales than teachers in other countries. Finally, younger teachers experienced more emotional exhaustion than older ones and primary education teachers experienced more personal accomplishment and less depersonalization than their counterparts in secondary education.     

Burnout in Greek teachers: Main findings and validity of the Maslach Burnout Inventory

Abstract

The factorial structure of the Maslach Burnout Inventory (Maslach and Jackson 1986) was investigated in a sample of 220 Greek teachers and was found to be similar to that reported by Maslach and Jackson. A job satisfaction measure was employed for the investigation of the discriminant validity of the burnout measure. Correlations between job satisfaction and the three burnout dimensions were found to be low to moderate. It is suggested that the relationship and the degree of overlap between emotional exhaustion and job satisfaction require further examination. Greek teachers reported lower levels of burnout on the emotional exhaustion and depersonalization scales than teachers in other countries. Finally, younger teachers experienced more emotional exhaustion than older ones and primary education teachers experienced more personal accomplishment and less depersonalization than their counterparts in secondary education.