Diagnostics for dependence within time series extremes

Summary. The analysis of extreme values within a stationary time series entails various assumptions concerning its long- and short-range dependence. We present a range of new diagnostic tools for assessing whether these assumptions are appropriate and for identifying structure within extreme events. These tools are based on tail characteristics of joint survivor functions but can be implemented by using existing estimation methods for extremes of univariate independent and identically distributed variables. Our diagnostic aids are illustrated through theoretical examples, simulation studies and by application to rainfall and exchange rate data. On the basis of these diagnostics we can explain characteristics that are found in the observed extreme events of these series and also gain insight into the properties of events that are more extreme than those observed.     

网络工期成本优化技术

本文提出利用列表和在表上逐步进行修改,最终得到工期成本优化问题的最优解的方法。该方法的特点是直观、易于操作。     

Creating a reference to a complex emergency situation using time series methods: war in Guinea-Bissau 1998-1999

Impacts of complex emergencies or relief interventions have often been evaluated by absolute mortality compared to international standardized mortality rates. A better evaluation would be to compare with local baseline mortality of the affected populations. A projection of population-based survival data into time of emergency or intervention based on information from before the emergency may create a local baseline reference. We find a log-transformed Gaussian time series model where standard errors of the estimated rates are included in the variance to have the best forecasting capacity. However, if time-at-risk during the forecasted period is known then forecasting might be done using a Poisson time series model with overdispersion. Whatever, the standard error of the estimated rates must be included in the variance of the model either in an additive form in a Gaussian model or in a multiplicative form by overdispersion in a Poisson model. Data on which the forecasting is based must be modelled carefully concerning not only calendar-time trends but also periods with excessive frequency of events (epidemics) and seasonal variations to eliminate residual autocorrelation and to make a proper reference for comparison, reflecting changes over time during the emergency. Hence, when modelled properly it is possible to predict a reference to an emergency-affected population based on local conditions. We predicted childhood mortality during the war in Guinea-Bissau 1998-1999. We found an increased mortality in the first half-year of the war and a mortality corresponding to the expected one in the last half-year of the war.     

Household strategies in the face of resource scarcity in coastal Ghana: are they associated with development priorities?

In many developing regions, women and young girls spend several hours daily in the collection of natural resources. Still the link between these household resource strategies and stakeholder perceptions of development priorities remains unexplored. This project examines this association with survey data representative of the adult population from Ghana’s Coastal Region. Although natural resource scarcity and the sustainability of resource use represent key development challenges, there are others (e.g., energy, sanitation, employment, and educational opportunities). As such, even in the face of natural resource scarcity, individuals may place greater importance on other dimensions of development, especially if household resource strategies are perceived as relatively efficient. The analytical focus here is on water and the results suggest that gender roles shape household water collection strategies, while also shaping these strategies’ perceived opportunity costs. Specifically, Ghanian adults more often see drinking water provision as their primary development need when water sources are distant and/or when male household members collect water (particularly male heads). In the end, I argue that social science inquiry benefits by contextualizing social dynamics within environmental context, particularly within cultural settings in which human subsistence is intimately tied to the state of the natural environment.     

从杜夫海纳的困境中突围——《审美经验现象学》中的文学作品理论

作为现象学美学经典文本的《审美经验现象学》对审美活动进行了深入的剖析,但令人遗憾的是,杜夫海纳在该书中却回避了对同为艺术作品的文学作品的分析,这种回避源自杜夫海纳对于语言优先性的坚持。如果从语言的陈述性入手,或许可以为文学理论的构建提供一个新的思路。     

北魏孝文帝定姓族制度散论

北魏孝文帝实施定姓族 ,首先 ,它既是北魏汉化政策的继续和发展 ,也是北魏历史发展的客观需要 ,在当时具有一定的现实意义 ;其次 ,姓族制度的实施在消除民族间的隔阂、加强北魏政权的统治以及提高鲜卑人的文化水平等方面也起了一定的积极作用 ;其三 ,姓族制度的实施与北魏政权的政治有密切的关系 ,不同时期所发挥的作用不同 ,应作具体分析 ,不能说姓族制对北魏政权的灭亡起了最直接、最主要的作用。     

反垄断法中相关市场的界定标准

相关市场是竞争法中的基础性概念,对所有限制竞争行为的讨论都必须以界定相关市场为基础。相关市场又分为相关产品市场、相关地理市场和相关时间市场。结合相关案例和经济学理论对三种市场进行讨论,可以为我国反垄断立法中关于相关市场的立法和执法提供借鉴。     

试论从“韬光养晦”到“和平崛起”的外交战略

“和平崛起”战略不仅是中国高层向国际社会的庄重承诺,更是社会主义中国的历史选择。这一战略是在同一时代主题、同一战略目标和同一利益要求下对邓小平“韬光养晦”和平外交思想的继承、丰富和发展。     

叙事文学与时间

通过分析不同时期东西方最具代表性的时间观,进而探讨时间观对叙述文学的发展所产生的影响。     

评货物所有权移转之立法例——兼论各国立法协调之可能性

货物所有权移转的时间问题 ,是货物买卖中的一个最为重要也是最为敏感的问题。本文采用比较法的研究方法 ,在分析与评价关于货物所有权移转的主要立法例的基础上 ,探讨各国立法协调之可能性。本文认为 ,交付主义为最佳选择模式 ;尽管关于货物所有权移转的时间采取的立法例不尽相同 ,但这绝对不意味着没有协调的可能性。就实际情况而言 ,各国或地区的有关立法对此问题的规定正在走向趋同 ,即采用交付主义或向交付主义靠拢。各国或地区立法之所以具有协调的可能性 ,这是由于当代社会经济的国际化、一体化的特点所决定的