Delay Estimation for Some Stationary Diffusion-type Processes

In this paper the asymptotic behaviour of the maximum likelihood and Bayesian estimators of a delay parameter is studied. The observed process is supposed to be the solution of a linear stochastic differential equation with one time delay term. It is shown that these estimators are consistent and their limit distributions are described. The behaviour of the estimators is similar to the behaviour of corresponding estimators in change-point problems. The question of asymptotical efficiency is also discussed.     

浅谈中药现代化的发展现状及对策

中药现代化是中药走向国际市场的必由之路.目前国内关于中药现代化的研究已取得较大成就,并得到国内外的广泛认同,但也存在一些问题和弱点,有待解决.文章主要从药材来源,中药的炮制,化学成分,制剂工艺,质量标准,药理和毒理以及临床不良反应等方面进行研究,并就此提出了相应的对策和建议.     

Interval Estimations for the Mean of the Generalized Poisson and Generalized Negative Binomial Distributions

In this article, we extend the Wald, score, skewness-corrected score, likelihood ratio, and mid-P intervals for the means of the generalized Poisson and generalized negative binomial distributions. These distributions are the members of the discrete version of the natural exponential family (NEF) with cubic variance function (CVF). Also, the coverage probabilities, the distal and mesial noncoverage probabilities, and the lengths of the proposed confidence intervals are estimated by means of a Monte Carlo simulation study. Finally, some practical examples are provided to show the applicability of the proposed intervals in applied studies.     

Male-to-Female Transgender Individuals Building Social Support and Capital From Within a Gender-Focused Network

ABSTRACT

The literature on male-to-female transgender myriad problems such individuals face in their day-to-day lives, including high rates of HIV/AIDS, addiction to drugs, violence, and lack of health care. These problems are exacerbated for ethnic and racial minority MTFs. Support available from their social networks can help MTFs alleviate these problems. This article explores how minority MTFs, specifically in an urban environment, develop supportive social networks defined by their gender and sexual identities. Using principles of community-based participatory research (CBPR), 20 African American and Latina MTFs were recruited at a community-based health care clinic. Their ages ranged from 18 to 53. Data were coded and analyzed following standard procedure for content analysis. The qualitative interviews revealed that participants formed their gender and sexual identities over time, developed gender-focused social networks based in the clinic from which they receive services, and engaged in social capital building and political action. Implications for using CBPR in research with MTFs are discussed.     

Robust estimation for finite populations based on a working model

A common scenario in finite population inference is that it is possible to find a working superpopulation model which explains the main features of the population but which may not capture all the fine details. In addition, there are often outliers in the population which do not follow the assumed superpopulation model. In situations like these, it is still advantageous to make use of the working model to estimate finite population quantities, provided that we do it in a robust manner. The approach that we suggest is first to fit the working model to the sample and then to fine-tune for departures from the model assumed by estimating the conditional distribution of the residuals as a function of the auxiliary variable. This is a more direct approach to handling outliers and model misspecification than the Huber approach that is currently being used. Two simple methods, stratification and nearest neighbour smoothing, are used to estimate the conditional distributions of the residuals, which result in two modifications to the standard model-based estimator of the population distribution function. The estimators suggested perform very well in simulation studies involving two types of model departure and have small variances due to their model-based construction as well as acceptable bias. The potential advantage of the proposed robustified model-based approach over direct nonparametric regression is also demonstrated.     

多媒体教学模式存在的问题及其对策

多媒体教学模式具有传统教学模式无法比拟的优越性,但在多媒体教学实践活动中也存在很多问题,为了保证教学质量和教学效率,要正确处理好多媒体教学模式和传统教学模式的关系.文章初步分析了多媒体教学模式存在的问题,并就有关问题提出了相应的策略.     

改性硅酸盐水泥的水化历程研究

将磷铝酸盐水泥熟料（简称：PALC）掺入硅酸盐水泥（简称：PC）对其进行改性，研究了不同磷铝酸盐水泥熟料掺量对改性硅酸盐水泥力学性能和水化历程的影响。研究结果表明，适宜的磷铝酸盐水泥熟料掺量（外掺3％）可以加速改性硅酸盐水泥的水化，提高其早期和后期强度；但掺量过多，由于磷铝酸盐水泥水化较快，产生的水化产物较致密，这些致密的水化产物包裹在C3S、C2S等水泥颗粒的外层，阻止了其进一步的水化，使改性水泥出现一个持续时间较长的第二诱导期，从而使表现出较慢的水化速率和较低的早期强度。     

高等学校数学实验课现状分析及对策

数学实验是学生借助数学软件对数学问题进行自我研究分析的过程。通过设置有趣而生动的问题让学生自己动手去做，使学生在学习的过程中体验数学的探索、发现和应用，从而充分发挥了数学实验课在数学教学中的作用，促进了教学改革。     

A Note on Nonparametric Regression with β-Mixing Sequences

Statistical risks of least-squares estimates of a regression function (possibly nonlinear) are studied under a β-mixing setup. The assumptions are minimal and are virtually the same as those of the i.i.d. case. The bounds obtained are optimal, up to a term of order log n. Similar results are also obtained for complexity regularized regression estimates in the presence of penalty functions.