Sequential Search and Selection Problem Under Uncertainty

This paper formulates and discusses a series of sequential decision problems of the following common structure: A decision alternative of multiple attributes‐that is, a job, an employee, or an investment alternative‐is to be selected within a certain fixed length of time. An unknown number of alternatives are presented sequentially, either deterministically or in a random manner. The decision maker can rank all the alternatives from best to worst without ties, and the decision to accept or reject an alternative is based solely on the relative ranks of those alternatives evaluated so far. The nonparametric sequential decision problem is first studied for a model involving a discrete time period and then generalized in terms of continuous time. Also considered is a variant of this problem involving a Bayesian estimation of (1) the uncertain probability of having an alternative at a given stage in the discrete‐time model and (2) the arrival rate of alternatives in the continuous‐time model. The optimal selection strategy that maximizes the probability of selecting the absolute best alternative is illustrated with the job search problem and the single‐machine job assignment problem.     

“Hedge Your Bets”: Technology’s Role in Young Gay Men’s Relationship Challenges

Technology is playing an increasingly pervasive role among young gay men in the process of meeting potential romantic or sexual partners. We investigated challenges posed by technology related to young gay men’s relationships. Focus groups (n = 9) of young gay men aged 18–24 (n = 43) were transcribed verbatim, and thematic analysis was used to identify two major themes regarding challenges to relationship development and maintenance. Subthemes include unrealistic expectations of relationships, inauthentic self-presentation online, sexual primacy over romance, increased opportunities for infidelity, and jealousy. The implications of this study for sexual education and sexual health promotion are discussed.     

经世致用与老子思想的融合--魏源《老子本义》思想剖析

魏源从今文经学经世致用的原则出发,对老子的思想进行了新诠解,并视<老子>为"救世之书".他又结合自己的时代特点,对老子的社会政治价值进行了深入挖掘,对"自然无为"、"无欲为体,无为为用"、"慈、俭、不敢为天下先"、"小国寡民"等思想作出了新的诠解,体现出强烈的忧患意识与救世情怀,实现了对老子思想的超越,也开启了近代道家思想研究的新阶段.     

Jack’d,a Mobile Social Networking Application: A Site of Exclusion Within a Site of Inclusion

User-generated smartphone applications have created a new level of virtual connectivity for gay males, one in which users can create profiles and meet other users as nearby or as far away as possible. For those within close proximity, the other users can be considered their “virtual neighbors.” Although the applications are theoretically designed to be places of inclusion and not exclusion, where any gay male with economic means can download an application, many profiles have been created that exclude other users. Through an examination of profiles on one such application, Jack’d, exclusion is found in the way users celebrate and reinforce ideas of traditional masculinity and denigrate and reinforce stereotypic ideas of femininity embodied by some gay men. Jack’d, and other user-generated smartphone applications, can be read as virtual neighborhoods where one is excluded based on their gender performance.     

习近平贫困治理重要论述的理论意蕴及在四川藏区的实践应用

习近平关于贫困治理的系列重要论述承载着丰富的理论意蕴：其一,改革创新是贫困治理的长效保障;其二,人民群众是贫困治理的基石和源泉;其三,精准扶贫是全面建成小康社会的必要路径。本文立足于习近平贫困治理重要论述的理论意蕴,构建了精准扶贫与精细化治理有效对接的理论分析框架,对四川藏区贫困治理的现状及问题进行了深入分析,指出在后精准脱贫阶段,进一步增强四川藏区扶贫实效,需要创新集聚启动机制、完善瞄准定位机制、构建利益联结机制、健全监测调控机制、探索益贫发展机制、构建应急机制。     

Probability models of chance fluctuations in spectra of astronomical sources with applications to X-ray absorption lines

The search for faint emission or absorption lines in astronomical spectra has received considerable attention in recent years, especially in the X-ray wavelength range. These features usually appear as a deficit or excess of counts in a single-resolution element of the detector, and as such they are referred to as unresolved fluctuations. The general problem under investigation is the probability of occurrence of chance fluctuations. A quantitative answer is necessary to determine whether detected fluctuations are a real (astronomical, in this case) signal, or if they can be attributed to chance. This application note provides a new comprehensive method to answer this question as function of the instrument's resolution, the wavelength coverage of the spectrum, the number of fluctuations of interest, and the confidence level chosen. The method is based on the binomial distribution and addresses also the probability of multiple simultaneous fluctuations. A critical aspect of the model is the a priori knowledge of the location of possible fluctuations, which significantly affects the probability of detection. In fact, a wider wavelength range for the ‘blind’ search of possible fluctuations results in a larger number of ‘tries’ for the detection of a fluctuation, lowering the overall significance of a specific feature. The method is illustrated with a case study and examples using X-ray data.     

Sur le langage et l’écriture en sociologie Brèves considérations théoriques et pratiques à partir de Bourdieu

After showing that language and writing are used as basic resources in sociology, this article seeks to identify issues raised by writing in sociology to produce the knowledge expected of this discipline as other social sciences. After considering the status of sociological knowledge and use of language that this knowledge requires, the article seeks to define the rules to be followed by sociologists in order to explain what it means in science. The arguments presented here differ from those developed in some post-modern theories, according to which sociology is after all only a matter of language, and sociologists are authors like novelists. The article is based on considerations developed in particular by Pierre Bourdieu.     

Unlocking Doors: Providing MSW Programs and Students with Educational “Keys” to Social Justice

ABSTRACT

How can social work educators identify what constitutes social justice as a practice, as a social work stance? How can we teach our students to recognize this stance, to work toward it, to practice it, and to live it? Symbolic interactionist Erving Goffman's concepts of keys and keying, as underscored in his work Frame Analysis, provide useful tools for helping students to recognize the value of social justice within social work educational encounters and to apply this value when they enter the field. The concepts of keys and keying can also help programs to assess and amplify their commitments to social justice.     

国外网络信息的发展与应用

美国具有强大的网络信息优势,在网络信息的发展趋势和应用方面也代表了国外网络信息的发展方向;日本在网络信息的发展和应用方面一直紧跟美国走在世界前列。以美国和日本为代表分析了发达国家信息化发展的社会环境和政策措施,指出了发展中国家如何面对机会和挑战,发展本国的信息化产业。