The analysis of incomplete data using stochastic covariates

In the development of many diseases there are often associated random variables which continuously reflect the progress of a subject towards the final expression of the disease (failure). At any given time these processes, which we call stochastic covariates, may provide information about the current hazard and the remaining time to failure. Likewise, in situations when the specific times of key prior events are not known, such as the time of onset of an occult tumour or the time of infection with HIV-1, it may be possible to identify a stochastic covariate which reveals, indirectly, when the event of interest occurred. The analysis of carcinogenicity trials which involve occult tumours is usually based on the time of death or sacrifice and an indicator of tumour presence for each animal in the experiment. However, the size of an occult tumour observed at the endpoint represents data concerning tumour development which may convey additional information concerning both the tumour incidence rate and the rate of death to which tumour-bearing animals are subject. We develop a stochastic model for tumour growth and suggest different ways in which the effect of this growth on the hazard of failure might be modelled. Using a combined model for tumour growth and additive competing risks of death, we show that if this tumour size information is used, assumptions concerning tumour lethality, the context of observation or multiple sacrifice times are no longer necessary in order to estimate the tumour incidence rate. Parametric estimation based on the method of maximum likelihood is outlined and is applied to simulated data from the combined model. The results of this limited study confirm that use of the stochastic covariate tumour size results in more precise estimation of the incidence rate for occult tumours.     

关于教育对经济增长抑制效应的思考

教育对经济增长的抑制效应是教育对经济增长双重效应的一个重要方面。本文从确认教育对经济增长的抑制效应的存在出发,分析了教育对经济增长抑制效应的具体情形,探讨了教育对经济增长抑制效应的存在机制。     

论"从日本奇迹到日本问题"

战后创造过经济奇迹的日本 ,在 2 0世纪的最后十年陷入了极其深重的经济危机。究其原因 ,一是独特的法人相互持股制度已从多方面对日本经济的发展形成了桎梏 ;二是银行与企业融合的主办银行制度在进入 80年代后出现了一系列问题 ;三是以终身雇佣制度为核心的企业人力资源管理体制显现出严重的机制性缺陷 ;四是双向式控制的公司治理结构的负作用越来越明显 ;五是政府强干预的经济管理体制的局限性逐渐暴露出来。     

吉林省地区间经济力差距分析

按照Kuznets倒U字假说,我国实现经济高速增长过程中,由于区域经济增长的不平衡性,导致了地区间经济力差距的扩大。吉林省为了尽可能地缩小地区间经济力的差距,以便促进地区的均衡发展,应该在省内形成以信息和高速公路网络为基础的共同市场。     

河南农业经济结构调整对农业劳动力的挑战

河南是农业大省,要使河南农业进一步发展,农民收入进一步增加,河南农业经济必须进行结构调整。农业经济结构调整的主体是农业劳动力,而农业劳动力素质,特别是农业劳动力文化素质的高低则成为河南农业经济结构调整的关键。文中重点分析了河南省农业劳动力文化素质的现状及与农业经济结构调整要求的差距,最后提出了提高河南省农业劳动力文化素质的对策。     

西部金融发展的路径选择探析

通过我国东、西部金融发展水平的比较，发现西部金融正处于一种迟缓发展状态，因而未能真正发挥出对区域经济的促进作用。经过分析，认为西部应选择供给引导型金融发展道路，主动通过金融先行发展来加速经济增长。     

“霸王条款”形成的博弈分析

霸王条款违背了市场经济自由、平等和公平的原则,严重侵害消费者权益。对霸王条款显失公平的判断可以通过经济分析的方法进行,分析其成因旨在为铲除霸王条款提供决策上的依据。     

A Two-dimensional Heat Transfer Model for Atmosphere-land System in the Lake-dominated Alaskan Arctic

1 Introduction Shallow tundra lakes are one of the dominating landscape features in the Alaskan Arctic. They typically cover 20% of the total area of the North Slope of Alaska, and up to about 40% in the coastal plain [1,2]. Many lakes are, in their entirety or in part, shallower than the maximum annual ice thickness, consequently, some ice freezes completely to the lake bottom, nevertheless, large areas of water are deeper than the maximum ice thickness and the ice remains afloat througho…     

FDI对我国经济增长的实证分析

就外商直接投资(FD I)对我国经济增长的影响这一焦点问题,国内学者从定性采用多指标和从定量使用传统的基于普通最小二乘法(O LS)下的计量经济模型两个方面进行了比较详尽的研究。本文在现有文献基础上进行了尝试性创新,使用O LS法进行回归分析时,考虑了数据的平稳性问题,进行了数据的平稳性检验,并运用科克伦-奥克特(C ochrane-O rcutt法)方法纠正了可能存在的虚假回归现象,从而使估计结果更加稳健,结论也更加合理。     

延边地方财政对区域经济增长的影响

在延边地方财政支出结构中,生产性支出的比重相对低,这对区域经济增长会产生短期效果影响。利用区域经济增长与地方财政支出之间因果关系模型实证分析延边地区的结果,证实了这一结论。为了区域经济的稳定增长,延边地区应适当提高生产性支出的比重。