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81.
We examined the effects of sexual arousal on cortical somatosensory evoked potentials (SEPs) elicited by electrical stimulation delivered to the skin over either the dorsal penile or posterior tibial nerve. The electrical stimuli were initiated by the subject pressing a button. In Experiment 1, a single stimulus was delivered immediately upon button press. In Experiment 2, a randomly spaced train of stimuli was delivered after a randomly varying delay. SEPs were obtained during (1) a baseline condition during which subjects viewed a non‐erotic videotape, (2) an arousal condition in which subjects viewed an erotic videotape, and (3) a post‐orgasm condition during which subjects again viewed the non‐erotic videotape. Amplitudes of SEP components elicited by stimulation of either nerve decreased with sexual arousal and tended to return towards baseline values in the post‐orgasm condition. The SEP components that showed these changes included slow potentials generated before and after stimulus delivery, as well as the vertex potentials, N100 and P200.  相似文献   
82.
This study examined separate and combined maternal and paternal use of spanking with children at age 3 and children's subsequent aggressive behavior at age 5. The sample was derived from a birth cohort study and included families (n = 923) in which both parents lived with the child at age 3. In this sample, 44% of 3-year-olds were spanked 2 times or more in the past month by either parent or both parents. In separate analyses, being spanked more than twice in the prior month at age 3, by either mother or father, was associated with increased child aggression at 5 years. In combined analyses, there was a dose–response association; the greatest risk for child aggression was reported when both parents spanked more than twice in the prior month (adjusted odds ratio: 2.01; [confidence interval: 1.03–3.94]). Violence prevention initiatives should target and engage mothers and fathers in anticipatory guidance efforts aimed at increasing the use of effective and non-aggressive child discipline techniques and reducing the use of spanking.  相似文献   
83.
本文对独立逆抽样设计下优势比的置信区间的构造进行了研究,包括三个已有的方法,以及本文引入的鞍点逼近方法。通过模拟比较了这四个方法给出的置信区间。模拟结果表明,基于鞍点逼近方法给出的置信区间不比另外三种方法差。并且在一些情况下表现还优于其它三个方法。  相似文献   
84.
The paper develops some objective priors for correlation coefficient of the bivariate normal distribution. The criterion used is the asymptotic matching of coverage probabilities of Bayesian credible intervals with the corresponding frequentist coverage probabilities. The paper uses various matching criteria, namely, quantile matching, highest posterior density matching, and matching via inversion of test statistics. Each matching criterion leads to a different prior for the parameter of interest. We evaluate their performance by comparing credible intervals through simulation studies. In addition, inference through several likelihood-based methods have been discussed.  相似文献   
85.
就住宅污水冒溢这一问题阐述其产生原因、常见解决方法和具体措施,再通过系统地分析排水系统的水流原理及水力计算并结合现行规范和地区规定,来确定新的排水系统和管径,从而从根本上解决和预防住宅污水冒溢这一现象的产生.  相似文献   
86.
Abstract

Covariance estimation and selection for multivariate datasets in a high-dimensional regime is a fundamental problem in modern statistics. Gaussian graphical models are a popular class of models used for this purpose. Current Bayesian methods for inverse covariance matrix estimation under Gaussian graphical models require the underlying graph and hence the ordering of variables to be known. However, in practice, such information on the true underlying model is often unavailable. We therefore propose a novel permutation-based Bayesian approach to tackle the unknown variable ordering issue. In particular, we utilize multiple maximum a posteriori estimates under the DAG-Wishart prior for each permutation, and subsequently construct the final estimate of the inverse covariance matrix. The proposed estimator has smaller variability and yields order-invariant property. We establish posterior convergence rates under mild assumptions and illustrate that our method outperforms existing approaches in estimating the inverse covariance matrices via simulation studies.  相似文献   
87.
The paper discusses a quantile-based definition for the well-known proportional odds model. We present various reliability properties of the model using quantile functions. Different ageing properties are derived. A generalization for the class of distributions with bilinear hazard quantile function is established and the practical application of this model is illustrated with a real-life data set.  相似文献   
88.
Decision making is a critical component of a new drug development process. Based on results from an early clinical trial such as a proof of concept trial, the sponsor can decide whether to continue, stop, or defer the development of the drug. To simplify and harmonize the decision‐making process, decision criteria have been proposed in the literature. One of them is to exam the location of a confidence bar relative to the target value and lower reference value of the treatment effect. In this research, we modify an existing approach by moving some of the “stop” decision to “consider” decision so that the chance of directly terminating the development of a potentially valuable drug can be reduced. As Bayesian analysis has certain flexibilities and can borrow historical information through an inferential prior, we apply the Bayesian analysis to the trial planning and decision making. Via a design prior, we can also calculate the probabilities of various decision outcomes in relationship with the sample size and the other parameters to help the study design. An example and a series of computations are used to illustrate the applications, assess the operating characteristics, and compare the performances of different approaches.  相似文献   
89.
Abstract

The Poisson distribution is here used to illustrate Bayesian inference concepts with the ultimate goal to construct credible intervals for a mean. The evaluation of the resulting intervals is in terms of “mismatched” priors and posteriors. The discussion is in the form of an imaginary dialog between a teacher and a student, who have met earlier, discussing and evaluating the Wald and score confidence intervals, as well as confidence intervals based on transformation and bootstrap techniques. From the perspective of the student the learning process is akin to a real research situation. The student is supposed to have studied mathematical statistics for at least two semesters.  相似文献   
90.
This paper introduces a parametric discrete failure time model which allows a variety of smooth hazard function shapes, including shapes which are not readily available with continuous failure time models. The model is easy to fit, and statistical inference is simple. Further, it is readily extended to allow for differences between subjects while retaining the ease of fit and simplicity of statistical inference. The performance of the discrete time analysis is demonstrated by application to several data sets.  相似文献   
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