Lassoing the Determinants of Retirement

This article uses Danish register data to explain the retirement decision of workers in 1990 and 1998. Many variables might be conjectured to influence this decision such as demographic, socioeconomic, financial, and health related variables as well as all the same factors for the spouse in case the individual is married. In total, we have access to 399 individual specific variables that all could potentially impact the retirement decision. We use variants of the least absolute shrinkage and selection operator (Lasso) and the adaptive Lasso applied to logistic regression in order to uncover determinants of the retirement decision. To the best of our knowledge, this is the first application of these estimators in microeconometrics to a problem of this type and scale. Furthermore, we investigate whether the factors influencing the retirement decision are stable over time, gender, and marital status. It is found that this is the case for core variables such as age, income, wealth, and general health. We also point out the most important differences between these groups and explain why these might be present.     

Power analysis for clustered non-continuous responses in multicenter trials

Power analysis for multi-center randomized control trials is quite difficult to perform for non-continuous responses when site differences are modeled by random effects using the generalized linear mixed-effects model (GLMM). First, it is not possible to construct power functions analytically, because of the extreme complexity of the sampling distribution of parameter estimates. Second, Monte Carlo (MC) simulation, a popular option for estimating power for complex models, does not work within the current context because of a lack of methods and software packages that would provide reliable estimates for fitting such GLMMs. For example, even statistical packages from software giants like SAS do not provide reliable estimates at the time of writing. Another major limitation of MC simulation is the lengthy running time, especially for complex models such as GLMM, especially when estimating power for multiple scenarios of interest. We present a new approach to address such limitations. The proposed approach defines a marginal model to approximate the GLMM and estimates power without relying on MC simulation. The approach is illustrated with both real and simulated data, with the simulation study demonstrating good performance of the method.     

基于扎根理论的茅山江南名山形象认知分析

江南名山是中国名山文化的重要组成部分,其形象的开发和利用为古代文人和知识分子所主导,是当前完善名山风景建设的关键因素,而诗词文本则是江南名山形象构建的见证。本文以江南名山茅山为研究案例,结合元代刘大彬所著《茅山志·金薤篇》中记载的茅山相关诗词及网络搜集的补充诗词为文本材料,运用扎根理论对文本内容进行三级编码,归纳形成包括山地、生物、天象、气象资源等在内的十五个初始范畴和自然资源、文化特征、审美活动、行为互动、建筑设施五个主范畴,进而利用文本分析软件ROST CM6进行词频分析、社会网络与语义网络分析、情感意象分析。分析发现诗词文本中自然资源构成了茅山风景区核心景观资源。情感意象分析发现,中性情感比重最大,"归隐"频次最高,反映出诗人普遍以茅山寄托隐居志向,积极情感多表达诗人对自然资源的由衷喜爱。最后构建江南名山形象塑造过程的模型,认为永嘉之乱后江南名山得到了发展,优越的自然条件作为风景要素,是形象认知的起点和自然供给力。宗教文化的发展进一步推动了山岳诗文的创作,二者构成重要的文化供给力。隐居和游观活动的兴盛则是江南名山文化吸引力的重要体现。总结得出了茅山江南名山形象,为后续江南名山形象认知的研究打下基础。     

人力资源能力建设与我国创新型国家的建立

建设创新型国家,关键是创新人才的培养和广泛参与,这需要通过人力资源能力建设来推动该目标的实现。在20世纪90年代的10年里,中国人力资源能力建设大幅度提高,但仍面临若干问题,为适应中国加快创新型国家建设的需要,需要借鉴发达国家在人力资源能力建设方面的经验,强化人力资源能力建设过程中的关键点。     

晚清民国时期蔗糖业视野下的广西城镇经济网络

晚清民国时期,广西蔗糖业经历了繁荣、衰落再发展的轨迹,通过商人的经营活动促进了城镇经济网络和蔗糖业的楔合,蔗糖业的发展推动了城镇经济网络的发展。蔗糖业和城镇经济网络的楔合促进了民族经济融合。     

民工城乡两栖型就业与城市化

本文从民工的城乡两栖型就业这个角度出发 ,重点分析了对现阶段城市化进程中民工城乡两栖型就业的特点 ,并对民工的城市化归宿问题作了一些探讨     

湖南抗战文化运动概略(上)

湖南抗战文化运动十分活跃,在中国抗战文化史上应占有重要地位。本文上篇从文化．名人汇聚、抗日团体与文化阵营、进步报刊及新闻出版、戏剧歌咏等文化活动诸多方面介绍了长沙抗战文化盛况。下篇概括介绍除长沙以外的湖南其它地区的抗战文化运动情况,并探讨了湖南抗战文化运动的经验和意义。     

湖南抗战文化运动概略（下）

长沙抗战文化运动盛况空前,衡阳、湘潭、邵阳、株洲、湘西、益阳、娄底、岳阳、常德、郴州等长沙以外的湖南各地抗战文化运动也风起云涌,从中可总结湖南抗战文化运动的经验和意义。     

Conditional design of the EWMA median chart with estimated parameters

The exponentially weighted moving average (EWMA) chart is often designed assuming the process parameters are known. In practice, the parameters are rarely known and need to be estimated from Phase I samples. Different Phase I samples are used when practitioners construct their own control chart's limits, which leads to the “Phase I between-practitioners” variability in the in-control average run length (ARL) of control charts. The standard deviation of the ARL (SDARL) is a good alternative to quantify this variability in control charts. Based on the SDARL metric, the performance of the EWMA median chart with estimated parameters is investigated in this paper. Some recommendations are given based on the SDARL metric. The results show that the EWMA median chart requires a much larger amount of Phase I data in order to reduce the variation in the in-control ARL up to a reasonable level. Due to the limitation of the amount of the Phase I data, the suggested EWMA median chart is designed with the bootstrap method which provides a good balance between the in-control and out-of-control ARL values.     

均势和平论剖析

均势是个理论内涵丰富,实践操作复杂的国际战略,从近代以来它一直为西方政治家、战略家和外交家所推崇,因为他们相信均势能够给“自然状态”下的国际社会带来和平愿景。本文对国际国内学术界关于和平与均势的定义、特征、分类以及均势的功用等方面所取得的研究成果进行梳理,对国际关系理论范式关于均势与和平互动解读的得失作一个客观性评价。