Quasi-Likelihood Approach to Bioavailability and Bioequivalence Analysis

The outcomes AUCT (area-under-curve from time zero to time t) of n individuals randomized to one of two groups TR or RT, where the group name denotes the order in which the subjects receive a test formulation (T) or a reference formulation (R), are used to assess average bioequivalence for the two formulations. The classical method is the mixed model, for example, proc mixed or proc glm with random statement in SAS can be used to analyze this type of data. This is equivalent to the marginal likelihood approach in a normal–normal model. There are some limitations for this approach. It is not appropriate if the random effect is not normally distributed. In this article, we introduce a hierarchical quasi-likelihood approach. Instead of assuming the random effect is normal, we make assumptions only about the mean and the variance function of the random effect. Our method is flexible to model the random effect. Since we can estimate the random effect for each individual, we can check the adequacy of the distribution assumption about the random effect. This method can also be used to handle high-dimensional crossover data. Simulation studies are conducted to check the finite sample performance of the method under various conditions and two real data examples are used for illustration.     

Focused Information Criterion and Model Averaging in Quantile Regression

In this article, we study model selection and model averaging in quantile regression. Under general conditions, we develop a focused information criterion and a frequentist model average estimator for the parameters in quantile regression model, and examine their theoretical properties. The new procedures provide a robust alternative to the least squares method or likelihood method, and a major advantage of the proposed procedures is that when the variance of random error is infinite, the proposed procedure works beautifully while the least squares method breaks down. A simulation study and a real data example are presented to show that the proposed method performs well with a finite sample and is easy to use in practice.     

An Exponential-Gamma Convolution Model for Background Correction of Illumina BeadArray Data

Illumina BeadArrays are becoming an increasingly popular Microarray platform due to its high data quality and relatively low cost. One distinct feature of Illumina BeadArrays is that each array has thousands of negative control bead types containing oligonucleotide sequences that are not specific to any target genes in the genome. This design provides a way of directly estimating the distribution of the background noise. In the literature of background correction for BeadArray data, the information from negative control beads is either ignored, used in a naive way that can lead to a loss in efficiency, or the noise is assumed to be normally distributed. However, we show with real data that the noise can be skewed. In this study, we propose an exponential-gamma convolution model for background correction of Illumina BeadArray data. Using both simulated and real data examples, we show that the proposed method can improve the signal estimation and detection of differentially expressed genes when the signal to noise ratio is large and the noise has a skewed distribution.     

为什么农民无法从“公司+农户”中受益

为了探究以“公司+农户”为主体的农业产业化经营蓬勃发展与农民增收乏力之间的矛盾,文章以江西省部分农业龙头企业和农户的调查资料为基础,从家庭经营规模、利益联结机制和龙头企业实力三个方面分析了导致目前农民无法受益的原因:以妇女和老人为农业生产主体的农村“空心化”现状使得参与农业产业化经营的农户家庭经营规模偏小;农民和公司的主体地位不对称,农民难以参与农产品加工、销售环节的利润分配,农户和公司之间是松散型利益联结机制;农业龙头企业普遍是小企业,生存的压力已经令其自顾不暇,即使有心也无力让为数众多的农户参与到有限利润的分配中来.     

The Changing Mode of Legal Regulation of Labor Relations in China

At present, Chinese labor relations operate under a unitary model of legal regulation in which labor law is applied to workers “as a whole, with everyone treated equally.” This causes a number of problems. In reality, due to constantly changing modes of employment and the flexibility of workers’ “affiliation,” forms of employment are highly diverse. In addition to regular employees, there are also “quasi-employees” (employee-like persons) whose affiliation is quite weak, and other special employees. This necessitates the updating of the legislative thinking behind labor laws. While holding fast to the assumption that workers are a vulnerable group, we should review the differences between different types of employee and draw up the corresponding regulations on the basis of specific situations. Where legislative technique is concerned, we should do away with the traditional one-size-fits-all legislative model in favor of a dedicated model that targets particular types of subject and particular circumstances. We should abandon the traditional old-fashioned model in which “all labor law provisions apply” or “no labor law provisions apply” and categorize employees in such a way as to provide special rules for quasi-employees, special employees and employees of special employers. The legal regulation of labor relations should be based on categorization and differential treatment.     

“主位”视角下光棍社会地位的再研究——基于江汉平原的经验调查

光棍在传统社会中成为一种依附性的力量,嵌入到村庄结构中。光棍是弱势的文化指涉始终是乡土社会实践的“非意外结果”。由此,学者通过“婚姻挤压”和“婚姻排斥”导演出光棍的“被迫性”问题。但是,随着差序格局的理性化和传统村落社区的解体,光棍的“弱势”意蕴逐渐得以“祛魅”。基于经验调查,本文从“主位”视角出发展开对光棍社会地位的再研究,从经济条件的优厚者、婚姻的高价者、家庭结构中的当家者、人情的积极互动者、关系和资源的拥有者五个方面来呈现出光棍较高的社会地位,打破光棍弱势之迷,光棍只是作为一种生活方式的选择而已,这样就将光棍研究进一步推向“主位选择”的纵深层面。     

超越学科与族群边界——访著名人类学者巫达教授

巫达教授在访谈中从他个人成长历程出发,谈到他在西南地区对彝族和藏族的研究以及对西南地区研究的看法,并进一步阐述了他对族群研究、语言人类学的研究方法和研究心得,探讨人类学和其他学科互动的实际意义以及人类学实践性操作的问题。     

“感情的批评主义”:李长之1930年代作家论研究

作为中国现代文学批评史上独具特色的批评家,"明日张胆"地用"感情的批评主义"为作家论之批评宗旨的李长之,在"感情的型"的美学尺度下,以情感体验中的审美感知与兼容理智的作家批评实践,标示出他1930年代作家论写作的独特魅力.显然,李长之所建构的以情感为中心、情感与识力并行不悖的作家批评范式,在丰富和拓展1930年代作家论的批评内涵的同时,亦对当时的作家论写作具有一定的体式意义.     

论我国自然资源产权制度改革

我国长期实行的粗放型、资源依赖型经济增长方式,已经产生了社会需要与资源短缺之间巨大的矛盾。破解这种难题,必须从自然资源的产权制度改革入手。自然资源产权既具有一般产权的共同特点,又具有自身的特殊性,如在产权安排、所有权界定、使用权界定等方面,就必须考虑到自然资源的复杂性。如果不能有效地对自然资源产权进行制度性安排,必然会产生“公地悲剧”。我国自然资源产权制度的改革,应该实现国家政策目标与微观经济主体行为目标的激励相容,同时实现国家生态效益得到激励并减少“政府失灵”与私人经济效益得到激励并减少“市场失灵”的双重目标。