Generalized phase I-II designs to increase long term therapeutic success rate

Designs for early phase dose finding clinical trials typically are either phase I based on toxicity, or phase I-II based on toxicity and efficacy. These designs rely on the implicit assumption that the dose of an experimental agent chosen using these short-term outcomes will maximize the agent's long-term therapeutic success rate. In many clinical settings, this assumption is not true. A dose selected in an early phase oncology trial may give suboptimal progression-free survival or overall survival time, often due to a high rate of relapse following response. To address this problem, a new family of Bayesian generalized phase I-II designs is proposed. First, a conventional phase I-II design based on short-term outcomes is used to identify a set of candidate doses, rather than selecting one dose. Additional patients then are randomized among the candidates, patients are followed for a predefined longer time period, and a final dose is selected to maximize the long-term therapeutic success rate, defined in terms of duration of response. Dose-specific sample sizes in the randomization are determined adaptively to obtain a desired level of selection reliability. The design was motivated by a phase I-II trial to find an optimal dose of natural killer cells as targeted immunotherapy for recurrent or treatment-resistant B-cell hematologic malignancies. A simulation study shows that, under a range of scenarios in the context of this trial, the proposed design has much better performance than two conventional phase I-II designs.     

住房攀比与居民消费

本文基于CFPS微观跟踪调查数据,从地位寻求角度分析了住房攀比行为对城镇家庭消费的影响。结果表明：①家庭对自身社会地位等级的主观评价与住房面积、消费水平、户主学历等因素呈显著的正相关关系;②住房面积攀比对城镇家庭消费有明显的抑制作用;③社会地位高的家庭的消费行为对其它家庭的示范效应显著,即中国城镇家庭存在向上攀比的地位寻求动机。     

收入风险、金融教育与家庭金融市场参与

运用中国城市居民消费金融调查数据,基于因果推断的分析框架,采用倾向分值匹配法研究了收入风险、金融教育对家庭金融市场参与的影响。研究发现,收入越稳定,家庭开展金融教育的概率越高;金融教育显著提高了家庭的金融市场参与;按收入风险将样本分组后,上述结论依然稳健,且金融教育对不同家庭金融市场参与的影响具有非对称性。在对家庭收入稳定性分类的基础上,有针对性地增加金融教育的供给,提升家庭整体的金融教育水平,有利于提高家庭金融市场参与度,优化家庭金融资产配置,进而改善家庭金融福利。     

Approximating the chromatic index of multigraphs

It is well known that if G is a multigraph then χ′(G)≥χ′^*(G):=max {Δ(G),Γ(G)}, where χ′(G) is the chromatic index of G, χ′^*(G) is the fractional chromatic index of G, Δ(G) is the maximum degree of G, and Γ(G)=max {2|E(G[U])|/(|U|−1):U⊆V(G),|U|≥3, |U| is odd}. The conjecture that χ′(G)≤max {Δ(G)+1,⌈Γ(G)⌉} was made independently by Goldberg (Discret. Anal. 23:3–7, 1973), Anderson (Math. Scand. 40:161–175, 1977), and Seymour (Proc. Lond. Math. Soc. 38:423–460, 1979). Using a probabilistic argument Kahn showed that for any c>0 there exists D>0 such that χ′(G)≤χ′^*(G)+c χ′^*(G) when χ′^*(G)>D. Nishizeki and Kashiwagi proved this conjecture for multigraphs G with χ′(G)>⌊(11Δ(G)+8)/10⌋; and Scheide recently improved this bound to χ′(G)>⌊(15Δ(G)+12)/14⌋. We prove this conjecture for multigraphs G with $\chi'(G)>\lfloor\Delta(G)+\sqrt{\Delta(G)/2}\rfloor$\chi'(G)>\lfloor\Delta(G)+\sqrt{\Delta(G)/2}\rfloor , improving the above mentioned results. As a consequence, for multigraphs G with $\chi'(G)>\Delta(G)+\sqrt {\Delta(G)/2}$\chi'(G)>\Delta(G)+\sqrt {\Delta(G)/2} the answer to a 1964 problem of Vizing is in the affirmative.     

《三国演义》接受的文化阐释

《三国演义》[1]的创作是作者个人心理与民族文化心理的一种集大成,而本书的接受过程也是在文化语境中产生的,在接受过程中,虽然表现出来的形式多种多样,但在这纷繁复杂的表象之外,其实还是有些文化含义贯穿始终,本文择其要者加以论述,分别是强烈的政治教化功能,积极进取的入世精神,深重的忧患意识。     

Hui Muslim‐Han Chinese Differences in Perceptions on Endogamy in Urban China

Using a survey data set (n?=?1,992) collected in Lanzhou, China, I examine the Hui?–?Han differences in perceptions on intermarriage. The questions I ask in this paper include: What is the extent of interethnic marriages in Lanzhou? Do the Hui and Han feel differently about interethnic marriage? Which ethnic group is more negative about Hui?–?Han marriages and why? Are perceptions about endogamy patterned by ethnicity or socio-economic status or both? I seek plausible answers to these questions in this paper. A preliminary analysis of the 2001 survey data shows a high degree of endogamy in Lanzhou. It also shows that the Hui are more negative about intermarriage than the Han. However, the ethnic differences in perceptions on intermarriage fade away with socio-economic variables controlled.     

略论文征明的造园思想

文征明在中国造园史上占有较为重要的一席之地,他所主持设计的拙政园迄今为止仍然保留着一开始的主要风格和特点。这说明文征明的造园思想自有其高明之处。具体而言,在拙政园的营建过程中,文征明的总体思路可基本概括为因地制宜、法乎自然,除此之外,文征明更注重赋予自然景观一种个性化的人生理想和价值观,并由此彰显出明代江南文人的精神追求和独立意识。     

汉初货币制度变革与经济结构的变动--兼谈张家山汉简《钱律》问题

本文在把握秦朝和西汉前期社会结构变迁的基础上,全面论述了西汉前期货币制度变迁的原因和历史作用。认为秦朝之统一货币之后,是经济结构的因素导致了商品经济的萎缩。详细考析了张家山汉简《钱律》以及相关内容。论证了刘邦、吕后、文帝、景帝时代的货币变革经济因素、政治因素的作用,体现了国家力量控制经济的内在逻辑及其互动关系。澄清了以往的某些误解。     

西方政治哲学的人性规定

人性是西方政治哲学的经典命题,不同政治哲学的人性规定决定其独特的理论品格。认为人性善的思想家通过道德召唤来完善个人的政治生活;认为人性恶的思想家以法治与规则保障政治生活的有序展开。出于对人性善恶之社会功能的权衡,西方政治哲学家通过建构政治制度来“抑恶扬善”,其对人与社会的关系的思考达到相当高的抽象水平,却脱离“现实的个人”与现实政治状况,马克思政治哲学以此为重要思想资源并以“改变世界”的“现实的运动”完成对西方政治哲学的现实超越。     

从哈佛学派、芝加哥学派到后芝加哥学派——反托拉斯与竞争政策的产业经济学理论基础的发展与展望

世界近现代经济史,尤其是欧美近现代经济史的主要曲调之一是与“马歇尔冲突”相关的所谓反托拉斯或竞争政策。整个反托拉斯过程是经济实践、经济理论与伦理观念交织作用、相互影响的过程。本文即试图从这样一个过程,通过分析反托拉斯与竞争政策的产业经济学理论基础——从哈佛学派、芝加哥学派再到后芝加哥学派的发展,再探反托拉斯的真谛。并依此反思我国反垄断法及相关政策的出台。