Perfect Forward Simulation via Simulated Tempering

Several authors discuss how the simulated tempering scheme provides a very simple mechanism for introducing regenerations within a Markov chain. In this article we explain how regenerative simulated tempering schemes provide a very natural mechanism for perfect simulation. We use this to provide a perfect simulation algorithm, which uses a single-sweep forward-simulation without the need for recursively searching through negative times. We demonstrate this algorithm in the context of several examples.     

Medcamp's Effect on Junior High School Students' Medical Career Self-Efficacy

Medcamp, a 3-day problem-based career intervention for students entering the 9th grade, implemented each of the 4 antecedents for self-efficacy. Ten boys and 35 girls participated in Medcamp; of these, 35 completed and returned the Medical Career Self-Efficacy Scales (developed by the authors for their study) both at the beginning and at the end of the program. Three scales measured specific self-efficacy (tasks students had performed during Medcamp), related self-efficacy (other tasks students would complete by the second year of medical school), and general self-efficacy (included lifestyle variables and study habits). Results demonstrated significant increases in self-efficacy on all 3 scales.     

A psychodynamic approach to the treatment of pathological gambling: Part I. Achieving abstinence

A psychodynamic approach emphasizes the meaning and consequences of one's behavior. After a brief review of the literature, the authors present the first of a two-part model for psychodynamic psychotherapy with pathological gamblers. In this first phase, the immediate goal is abstinence, and five strategies for obtaining it are discussed. These consist of 1.) breaking through the denial 2.) confronting omnipotent defenses 3.) interrupting the chasing cycle 4.) identifying reasons for gambling, and 5.) motivating the patient to become an active participant in treatment. An argument is made for integrating a traditional psychodynamic approach with an addictions model.     

Scaling limits for the transient phase of local Metropolis–Hastings algorithms

Summary.  The paper considers high dimensional Metropolis and Langevin algorithms in their initial transient phase. In stationarity, these algorithms are well understood and it is now well known how to scale their proposal distribution variances. For the random-walk Metropolis algorithm, convergence during the transient phase is extremely regular—to the extent that the algo-rithm's sample path actually resembles a deterministic trajectory. In contrast, the Langevin algorithm with variance scaled to be optimal for stationarity performs rather erratically. We give weak convergence results which explain both of these types of behaviour and practical guidance on implementation based on our theory.     

Use of an ISO 14000 Option in Implementing EPA's Rule on Risk Management Programs for Chemical Accidental Release Prevention

EPA's rule of Risk Management Programs for Chemical Accidental Release Prevention applies to facilities that manufacture, process, use, store, or otherwise handle regulated substances at or above specified threshold quantities. EPA estimates that approximately 66,000 facilities nationwide will be regulated under the rule. This paper examines the use of a structured ISO 14000 mechanism as option-regulated facilities could elect for implementation of the rule. Under the ISO 14000 option, facilities would commit to additional obligations regarding information disclosure, discussions with potentially affected publics, and timely correction of deficiencies noted in annual ISO 14000 audits of their compliance with the Risk Management Program they submit to the EPA under the rule. In return, facilities would be granted significant relief in regard to both EPA audit frequency and the penalties that might be applied for any items of noncompliance with the rule noted during the course of implementing agency reviews of the facility. The paper concludes with a discussion of the advantages and disadvantages of this option to potentially affected stakeholders.     

Disability management and psychosocial rehabilitation: considerations for integration

Disability management strategies have been successful in preventing or accommodating physical disabilities in the workplace. Similar success has not been realized in the realm of psychological/mental health related disabilities. Integration of the principles and strategies of psychosocial rehabilitation and disability management programs can assist employers to control costs related to psychological/mental health disabilities and protect individual workers employability.     

Behavioral problems of special needs adopted children

Parents of 757 special needs adoptees completed the behavior problems section of the Achenbach Child Behavior Checklist. Significant behavioral problems were not indicated for those children aged 4–5 at the time of the study. For children aged 6 to 16, behavioral problem scores were elevated on the two major CBC scales, externalizing (aggressive, acting-out behavior) and internalizing (withdrawn, inhibited behavior). The degree of elevation was greater for externalizing. Elevated scores were also observed on the total behavioral problems scale and, in particular, on hyperactivity sub-scales.     

Adoption outcomes for children with handicaps.

About 800 families who had adopted children with special needs responded to a mailed survey. Most reported good adoption outcomes. The presence of a handicap--vision, hearing, or physical impairment, mental retardation, or serious medical condition--was not an important factor influencing outcome.     

Analysis of the Gibbs sampler for a model related to James-Stein estimators

We analyse a hierarchical Bayes model which is related to the usual empirical Bayes formulation of James-Stein estimators. We consider running a Gibbs sampler on this model. Using previous results about convergence rates of Markov chains, we provide rigorous, numerical, reasonable bounds on the running time of the Gibbs sampler, for a suitable range of prior distributions. We apply these results to baseball data from Efron and Morris (1975). For a different range of prior distributions, we prove that the Gibbs sampler will fail to converge, and use this information to prove that in this case the associated posterior distribution is non-normalizable.