Catalogue of Group Structures for Three-level Fractional Factorial Designs

Taguchi (1959) introduced the concept of split-unit design to sort the factors into different groups depending upon the difficulties involved in changing the levels of factors. Li et al. (1991) renamed it as split-plot design. Chen et al. (1993) have given a catalogue of small designs for two- and three-level fractional factorial designs pertaining to a single type of factors. Aggarwal et al. (1997) have given a catalogue of group structure for two-level fractional factorial designs developed under the concept of split-plot design. In this paper, an algorithm has been developed for generating group structure and possible allocations for various 3^n-k fractional factorial designs.     

中国加入八国集团研究

八国集团对世界事务的影响举足轻重,中国对于是否加入八国集团表现的顾虑重重。究其原因,一是担心八国集团会架空联合国;二是中国考虑到自己是一个发展中国家,而八国集团从本质上来说是一个富国俱乐部;三是八国集团曾经在1989年制裁过我们。但是,我们加入八国集团却有许多好处:一是可以更好的改善中美关系;二是可以吸引和争取更多的投资和贷款;三是可以从八国集团的内部影响八国集团的决策;四是符合我们的大国外交战略。相反,如果我们长期远离八国集团,就可能在将来被边缘化。在加入的方式上,中国可以先以观察员的身份列席八国首脑会议,等待合适时机,正式加入。     

桐城文派"中兴"的一场大气磅礴的"宣言"--曾国藩《欧阳生文集序》析论

曾国藩千字文使日趋衰弱的桐城派回光返照,并由此“中兴”,而名声大振。行文表达创建湘乡派的“心声”,企图重振桐城文雄风。顺应时代剧变的需要,提出“文章与世变相因”文学理论,注入“经国济民”现实内容,以桐城文章来倡导洋务,铸就湘乡派卫道成仁的军魂,使文学发挥其社会功能。全文颇得桐城派作文之精髓,亦体现曾氏为文“气盛”的文章风格。     

Sequential Hypothesis Tests for Identifying the Minimum Dose with a Threshold Effect

We propose a procedure to identify a lowest dose having greater effect than a threshold dose under the assumption of monotonicity of dose mean response in dose response test. So, we use statistics based on contrasts among sample means and apply a group sequential procedure to our procedure to identify effectively the dose. If we can identify the dose at an early step in the sequential test, since we can terminate the procedure with a few observations, the procedure is useful from an economical point of view. In a simulation studies, we compare the superiority among these procedures based on three contrasts.     

Re-Defining the Who,When, and Where of Mentoring for Professional Statisticians

Organizations tailor their mentoring strategies to accommodate internal resources and preferences, producing different approaches in academic, government, and corporate environments. Across these settings, three common barriers impede effective mentoring of statisticians: overspecialization, time constraints, and geographic dispersion. The authors share mentoring strategies that have emerged at their organization, Mathematica Policy Research, to overcome these obstacles. Practices include creating a methodology working group to unite researchers with diverse backgrounds, integrating mentoring into existing workflows, and harnessing modern technological infrastructure to facilitate virtual mentoring. Although these strategies emerged within a specific professional context, they suggest opportunities for statisticians to expand the channels through which mentorship can occur.     

“无直接利益冲突”的网络发生机制

近年来,"无直接利益冲突"现象在我国似乎形成一种所谓"涟漪效应",其产生的深层根源在于社会分配的不公平及与之相联系的群体异质不公平感的普遍存在;其次也与利益表达机制的不畅通有关。在其产生的过程中,事件触发与演化的关联性往往是通过驱动机制、认同机制、社会比较与自我展示机制和说服争辩机制交互作用表现出来的。在信息时代,"无直接利益冲突"的这些相关发生机制往往与网络极化效应直接相关,即"无直接利益冲突"极易导致网络极化效应的产生,而网络极化效应也促使了"无直接利益冲突"的扩散。而这种双向互动的过程,正是"无直接利益冲突"网络发生机制的作用过程。由此,应给予充分重视。     

Extending systems thinking in planning and evaluation using group concept mapping and system dynamics to tackle complex problems

Group concept mapping (GCM) has been successfully employed in program planning and evaluation for over 25 years. The broader set of systems thinking methodologies (of which GCM is one), have only recently found their way into the field. We present an overview of systems thinking emerging from a system dynamics (SD) perspective, and illustrate the potential synergy between GCM and SD. As with GCM, participatory processes are frequently employed when building SD models; however, it can be challenging to engage a large and diverse group of stakeholders in the iterative cycles of divergent thinking and consensus building required, while maintaining a broad perspective on the issue being studied. GCM provides a compelling resource for overcoming this challenge, by richly engaging a diverse set of stakeholders in broad exploration, structuring, and prioritization. SD provides an opportunity to extend GCM findings by embedding constructs in a testable hypothesis (SD model) describing how system structure and changes in constructs affect outcomes over time. SD can be used to simulate the hypothesized dynamics inherent in GCM concept maps. We illustrate the potential of the marriage of these methodologies in a case study of BECOMING, a federally-funded program aimed at strengthening the cross-sector system of care for youth with severe emotional disturbances.     

Engaging children and youth in research and evaluation using group concept mapping

Group concept mapping is a systematic methodology that recognizes participants’ expertise in their own experiences. In this approach, participants share their diverse knowledge and interpret the data generated by all group members. This approach uniquely blends quantitative and qualitative techniques to create illustrative, structured conceptualizations. In this article, we describe the steps in group concept mapping and report feedback on this method from 37 children and youth who participated in group concept mapping studies. We recommend group concept mapping as an engaging way to involve children and youth in research and evaluation activities.     

Evidence of bias in the Eurovision song contest: modelling the votes using Bayesian hierarchical models

The Eurovision Song Contest is an annual musical competition held among active members of the European Broadcasting Union since 1956. The event is televised live across Europe. Each participating country presents a song and receive a vote based on a combination of tele-voting and jury. Over the years, this has led to speculations of tactical voting, discriminating against some participants and thus inducing bias in the final results. In this paper we investigate the presence of positive or negative bias (which may roughly indicate favouritisms or discrimination) in the votes based on geographical proximity, migration and cultural characteristics of the participating countries through a Bayesian hierarchical model. Our analysis found no evidence of negative bias, although mild positive bias does seem to emerge systematically, linking voters to performers.