A Class of Efficient Non-parametric K-sample Tests for Multivariate Counting Processes with Frailties

A K -sample testing problem is studied for multivariate counting processes with time-dependent frailty. Asymptotic distributions and efficiency of a class of non-parametric test statistics are established for certain local alternatives. The concept of efficiency is to show that for every non-parametric test in this class, there is a parametric submodel for which the optimal test has the same asymptotic power as the non-parametric one. The theory is applied to analyse a diabetic retinopathy study data set. A simulation study is also presented to illustrate the theory     

How well is debt managed by nonprofits?

Little is known about why nonprofits accrue debt, how much they owe, and whether the funds they borrow are used productively. This article distinguishes between productive, problematic, and deferred debt. Employing a data base representative of 114,726 tax-filing charitable nonprofits in the United States in 1986, it examines the pervasiveness of nonprofit debt and the relation between this debt and nonprofit financial health. The analysis finds that over 70 percent of the nonprofits hold debt, the distribution of this debt is highly concentrated, and the level of debt and leverage varies with asset size and type of activity. Nonprofits with higher leverage and absolute debt levels are financially healthier than those with lower levels. While the analysis does not determine whether financially stronger nonprofits are better able to borrow, the results support the view that borrowing in the nonprofit sector is economically efficient.     

关于社会福利制度的深层次思考

效率和公平是社会福利的两大准则 ,整个人类历史可以说就是一个不断追求效率和公平的历史 ,而其中针对社会弱势群体进行的收入和服务保障更是一个超社会形态的课题 ,是一个关乎人类社会福利的重要问题。针对中国的实际情况 ,本文中所讨论的社会福利制度被限定在“剩余福利模式”上。在对中外社会福利制度的起源及其理论发展进行考察的基础上 ,作者指出 :社会福利的提供应是制度化的政府职责 ,它的实施不仅能有效地保护社会弱势群体 ,还有利于全社会秩序的稳定和经济增长目标的实现 ;在中国目前财政收入相对不足的情况下 ,政府应充分利用社会资源、调动社会力量、推进立法、加紧培育行业组织和非赢利社会组织 ,以达到完善社会福利制度、有效保护社会弱势群体之目的。     

动力减振器最优参数的非线性回归和若干问题

本文采用最优化方法求得考虑生系统阻尼的动力减振器最优参数集，并对此参数集进行非线性回归，得到了便于动力减振器最优设计的回归曲线族。本文还对现有的主系统无阻尼时动力减振器最优参数公式进行了讨论，指出了这些公式的局限性，并根据本文的结果给出了应用范围更广泛的改进公式。     

One-dimensional optimal bounded-shape partitions for Schur convex sum objective functions

Consider the problem of partitioning n nonnegative numbers into p parts, where part i can be assigned n_i numbers with n_i lying in a given range. The goal is to maximize a Schur convex function F whose ith argument is the sum of numbers assigned to part i. The shape of a partition is the vector consisting of the sizes of its parts, further, a shape (without referring to a particular partition) is a vector of nonnegative integers (n₁,..., n_p) which sum to n. A partition is called size-consecutive if there is a ranking of the parts which is consistent with their sizes, and all elements in a higher-ranked part exceed all elements in the lower-ranked part. We demonstrate that one can restrict attention to size-consecutive partitions with shapes that are nonmajorized, we study these shapes, bound their numbers and develop algorithms to enumerate them. Our study extends the analysis of a previous paper by Hwang and Rothblum which discussed the above problem assuming the existence of a majorizing shape. This research is partially supported by ROC National Science grant NSC 92-2115-M-009-014.     

TOT项目融资中国有资产转让定价的博弈分析

本文以TOT项目融资方式为对象,运用博弈的方法,从合理分配国有资产经营期内增值收入的角度出发,得出这样的结论,在国有资产转让过程中,政府与私营资本之间的谈判是一系列复杂的博弈过程,在博弈中政府的最优行为是对国有资产转让进行招标,同时给予某一招标企业一定的中标优先权,这样政府能够较现行的国有资产转让方式获得更多的收益.     

城镇化视角下的土地流转影响因素研究——基于安徽5个市的农户调研数据

影响土地流转意愿的因素主要包括制度因素、经济因素、政策因素等.本文在城镇化背景下,基于农户角度,通过入户调查和logistic回归模型,研究家庭所在区域、城市购房打算等社会化因素,和土地收入、土地社会保障等土地功能因素对土地流转意愿产生的影响.研究结果表明,农户的社会化因素和土地功能因素对土地流转意愿均产生显著影响.     

透视区块链技术在经济和金融领域的应用

文章对区块链技术的基本逻辑和特征进行分析,探讨该项技术在经济和金融领域应用的优势,在此基础上对区块链技术在发达国家和发展中国家的前沿应用进行了案例分析,最后,结合我国目前区块链技术在经济和金融领域的应用过程中出现的一些问题,提出区块链经济的健康发展需要政府监管部门的正确引导。偏离实体经济需要和规避监管的伪创新不仅不能助推我国经济健康有序地增长,还会对我国金融市场的稳定运行带来极大的隐患。     

政府主导型景区开发中居民社会关系与乡村居民利益获取研究

人类活动具有社会性并在生产生活中产生各种关系,诸种关系不是杂乱无章的堆积,而是具有一定秩序与规律的有机整体,这一整体就是社会关系系统.在政府主导型景区开发中,政府通过政治关系运用政治权力主导机构设置、资金投入、资产补偿等景区开发活动,直接或间接影响利益分配.政府主导可能导致乡村社区丧失景区控制权;规划团队及规划方案使乡村社区核心景点和非景点区域利益获取出现分化,引发乡村社区利益空间秩序发生变化.研究发现,在社会关系影响下,各利益相关者在乡村社区展开博弈,导致社区生产空间和旅游利益分配非均衡发展;社区居民与其他景区利益相关者的关联性及关联程度影响着社区居民的利益获取.     

Assessing Risk‐Based Upper Limits of Melamine Migration from Food Containers

Melamine contamination of food has become a major food safety issue because of incidents of infant disease caused by exposure to this chemical. This study was aimed at establishing a safety limit in Taiwan for the degree of melamine migration from food containers. Health risk assessment was performed for three exposure groups (preschool children, individuals who dine out, and elderly residents of nursing homes). Selected values of tolerable daily intake (TDI) for melamine were used to calculate the reference migration concentration limit (RMCL) or reference specific migration limit (RSML) for melamine food containers. The only existing values of these limits for international standards today are 1.2 mg/L (0.2 mg/dm²) in China and 30 mg/L (5 mg/dm²) in the European Union. The factors used in the calculations included the specific surface area of food containers, daily food consumption rate, body weight, TDI, and the percentile of the population protected at a given migration concentration limit (MCL). The results indicate that children are indeed at higher risk of melamine exposure at toxic levels than are other groups and that the 95th percentile of MCL (specific surface area = 5) for children aged 1–6 years should be the RMCL (0.07 mg/dm²) for protecting the sensitive and general population.