Modified pseudo-likelihood estimator of the overdispersion parameter in Poisson mixture models

There are a variety of methods available for analyzing count data exhibiting extra-Poisson variation. Those based on quasi-likelihood, in particular, have gained tremendous popularity. In this paper, several moment estimators are compared. A new estimator, based on a modification of the pseudo-likelihood approach, is introduced and shown to perform very well when the overdispersion is not large, even if the sample size is very small.     

Prediction and Prevention of Child Abuse and Neglect

A high-risk population was successfully identified by the use of perinatal screening procedures. These children encountered significantly different parenting practices than the low-risk "control" group. There were also significant differences between "High-Risk" and "Low-Risk" families on issues concerning social adjustment and mother/infant attachment. Five children in a "High-Risk Nonintervene" group required hospitalization for serious injuries thought to be secondary to abnormal parenting practices. There were no such hospitalizations in either a High Risk Intervene group or a Low Risk group. Labordelivery observations, and postpartum interviews and observations provided the most accurate predictive information; prenatal interviews and questionnaires did not add significantly. Perinatal assessment and simple intervention with families at high risk for abnormal parenting practices significantly improves the infants' chances for escaping serious hospitalized physical injury.     

Ebola Virus Dose Response Model for Aerosolized Exposures: Insights from Primate Data

This study develops dose–response models for Ebolavirus using previously published data sets from the open literature. Two such articles were identified in which three different species of nonhuman primates were challenged by aerosolized Ebolavirus in order to study pathology and clinical disease progression. Dose groups were combined and pooled across each study in order to facilitate modeling. The endpoint of each experiment was death. The exponential and exact beta-Poisson models were fit to the data using maximum likelihood estimation. The exact beta-Poisson was deemed the recommended model because it more closely approximated the probability of response at low doses though both models provided a good fit. Although transmission is generally considered to be dominated by person-to-person contact, aerosolization is a possible route of exposure. If possible, this route of exposure could be particularly concerning for persons in occupational roles managing contaminated liquid wastes from patients being treated for Ebola infection and the wastewater community responsible for disinfection. Therefore, this study produces a necessary mathematical relationship between exposure dose and risk of death for the inhalation route of exposure that can support quantitative microbial risk assessment aimed at informing risk mitigation strategies including personal protection policies against occupational exposures.     

Predictive Inference and Scientific Reproducibility

ABSTRACT

Most statistical analyses use hypothesis tests or estimation about parameters to form inferential conclusions. I think this is noble, but misguided. The point of view expressed here is that observables are fundamental, and that the goal of statistical modeling should be to predict future observations, given the current data and other relevant information. Further, the prediction of future observables provides multiple advantages to practicing scientists, and to science in general. These include an interpretable numerical summary of a quantity of direct interest to current and future researchers, a calibrated prediction of what’s likely to happen in future experiments, a prediction that can be either “corroborated” or “refuted” through experimentation, and avoidance of inference about parameters; quantities that exists only as convenient indices of hypothetical distributions. Finally, the predictive probability of a future observable can be used as a standard for communicating the reliability of the current work, regardless of whether confirmatory experiments are conducted. Adoption of this paradigm would improve our rigor for scientific accuracy and reproducibility by shifting our focus from “finding differences” among hypothetical parameters to predicting observable events based on our current scientific understanding.     

Association between sarcopenia and erectile dysfunction in males with type II diabetes mellitus

Background: The prevalence rates for both sarcopenia and erectile dysfunction (ED) gradually increase in middle-aged and elderly diabetic male population and they impair physical functioning, sexual functioning, and quality of life. The aim of the present study was to evaluate the sarcopenia in patients with diabetic ED.

Methods: The study included 98 male patients with type II diabetes mellitus (DM) aged 18–80?years. Blood chemistry and hormone levels were obtained. The International Index of Erectile Function (IIEF-5) questionnaire was administered to the patients. The patients were divided into three groups according to the IIEF-5 score; a score of 5–10 points indicated severe ED, a score of 11–20 indicated moderate ED, and a score of 21–25 points indicated no ED. The muscle mass, handgrip strength, timed up and go test, upper mid-arm circumference, calf circumference, and body mass index were obtained. The statistical analysis was performed using MedCalc Statistical Software version 12.7.7. All parameters were compared between the three groups.

Results: Of 98 patients included in the study, 84 patients had severe sarcopenia, 13 had moderate sarcopenia, while only one patient had normal muscle mass. The mean age was 56.59?±?11.46?years. When patients were divided into three groups according to IIEF-5 score, 38 had severe ED, 39 had moderate ED, and 21 had no ED. There was a significant difference between the three groups in terms of handgrip strength, timed up and go test scores, upper mid-arm circumference, and calf circumference (p?Conclusions: Although muscle mass remains unchanged, muscle strength and physical performance decrease in diabetic ED patients. Diabetic patients with severe and moderate ED have lower muscle strength and physical performance.     

THERAPIST PHYSICAL ATTRACTIVENESS: AN UNEXPLORED INFLUENCE ON CLIENT DISCLOSURE

Existing research indicates that clients perceive facially attractive therapists as more competent, trustworthy, genuine, and effective than less attractive therapists. No Studies exist to help explain how the therapist's attractiveness influences a client's self-disclosure. Participants (n = 241) were randomly assigned to one of eight experimental groups to test the interaction of the therapist's attractiveness, client's gender, the nature of presenting problem, and the client's comfort with disclosing in a hypothetical couple therapy scenario. Analysis of variance procedures established that most participants reported feeling more comfortable disclosing a benign (communications) problem than a potentially embarrassing (sexual) problem, and more comfortable disclosing problem to an attractive than to a less attractive female therapist. Therapists are encouraged to understand the power attractiveness may have in their own and their client's lives     

Saturated main-effect designs for factorial experiments

The results of a computer search for saturated designs for 2ⁿ factorial experiments with n runs is reported, (where n = 2 mod 4). A complete search of the design space is avoided by focussing on designs constructed from cyclic generators. A method of searching quickly for the best generators is given. The resulting designs are as good as, and sometimes better than, designs obtained via search algorithms reported in the literature. The addition of a further factor having three levels is also considered. Here, too, a complete search is avoided by restricting attention to the most efficient part of the design space under p-efficiency.     

“刘易斯转折点”假象及其对“人口红利”释放的冲击

本文分析了当前普遍范围的用工荒是由于实际工资低于保留工资引起的农民工用脚投票结果。在此利用新家庭经济学单一模型理论分析这种经济行为是与简单单一个体预期效用最大化的经济行为相区别;农户以家庭为单位在金融资本及现代教育人力资本短缺的情况下通过家庭成员劳动力资本对外投资实施风险规避,在家庭内部实现收入分享,风险共担。这种经济行为带来的在工业制造和农业无法有效释放人口红利的结果,最终导致用工荒和环境负外部性以资本替代劳动的现代农业生产。