Sampled autocovariance and autocorrelation results for linear time processes

We derive an exact formula for the covariance between the sampled autocovariances at any two lags for a finite time series realisation from a general stationary autoregressive moving average process. We indicate, through one particular example, how this result can be used to deduce analogous formulae for any nonstationary model of the ARUMA class, a generalisation of the ARIMA models. Such formulae then allow us to obtain approximate expressions for the convariances between all pairs of serial correlations for finite realisations from the ARUMA model. We also note that, in the limit as the series length n → ∞, our results for the ARMA class retrieve those of Bartlett (1946). Finally, we investigate an improvement to the approximation that is obtained by applying Bartlett's general asymptotic formula to finite series realisations. That such an improvement should exist can immediately be seen by consideration of out results for the simplest case of a white noise process. However, we deduce the final improved approapproximation, for general models, in two ways - from (corrected) results due to Davies and Newbold (1980), and by an alternative approach to theirs.     

Testing Serial Correlation in Partially Linear Single-Index Errors-in-Variables Models

In this article, we propose two test statistics for testing the underlying serial correlation in a partially linear single-index model Y = η(Z ^τα) + X ^τβ + ? when X is measured with additive error. The proposed test statistics are shown to have asymptotic normal or chi-squared distributions under the null hypothesis of no serial correlation. Monte Carlo experiments are also conducted to illustrate the finite sample performance of the proposed test statistics. The simulation results confirm that these statistics perform satisfactorily in both estimated sizes and powers.     

城市快速公交系统的发展及我国的应用

城市快速公交系统作为一种新型的城市公共交通系统以其独有特征在世界范围内得到广泛推广。介绍BRT系统的产生背景及在国内外的发展现状;在探究BRT系统的特点及其技术特征的基础上研究我国城市BRT系统规划应该遵循的原则及发展BRT系统的模式选择。     

A new mathematical approach for the estimation of the AUC and its variability under different experimental designs in preclinical studies

The aim of the present work was to develop a new mathematical method for estimating the area under the curve (AUC) and its variability that could be applied in different preclinical experimental designs and amenable to be implemented in standard calculation worksheets. In order to assess the usefulness of the new approach, different experimental scenarios were studied and the results were compared with those obtained with commonly used software: WinNonlin® and Phoenix WinNonlin®. The results do not show statistical differences among the AUC values obtained by both procedures, but the new method appears to be a better estimator of the AUC standard error, measured as the coverage of 95% confidence interval. In this way, the new proposed method demonstrates to be as useful as WinNonlin® software when it was applicable. Copyright © 2011 John Wiley & Sons, Ltd.     

科技期刊中3个与范围有关的问题

科技期刊中描述范围时应规范使用浪纹线和一字线,表示起止作用时,浪纹线是数值范围符号,而一字线用于连接地名或方位名词,或相关的时间.英文论文中连接序号范围的是连接号“－”和“from…to…”.在描述变量取值范围时,建议在有2个变量且为同一取值范围的情况下,分开各自用数学运算符连接或用区间表示更简洁。     

公交车载摄像监控的非行政执法性分析

目前对于公交车载摄像监控是否可以作为道路交通管理部门对违章车辆行政执法的证据这一问题,笔者认为,我国交通技术监控设备的法定设置主体是道路交通安全部门,公交公司的车载监控设备属于企业内部管理监控设备。在目前情况下,公交车载摄像监控不具有行政执法性,其监控资料不能作为道路交通管理部门对违章占道车辆进行行政执法的证据。     

Long Distance Bus Travel: Insights for Social Work Practice

Long distance bus travel is a primary mode of intercity and nationwide transportation in the United States. Social work clients frequently rely on long distance bus travel to relocate, access treatment programs, seek employment, and garner support from family and friends. Previous research suggests difficulties associated with client travel contribute to delays in care and poorer intervention outcomes. However, research examining cultural, physical, and social aspects of long distance bus travel is sparse. In this study, characteristics of long distance bus travel ridership, stations, stops, employees, buses, rules, norms, and activities are identified and described. Grounded in practice focused research and through participant observation, data from a one-way long distance bus trip originating in a Midwestern city and ending in a large Eastern metropolitan city are reported using a systems orientation. Important themes (e.g., expense, stress, communication, human needs, substance use, authority, and diversity) are identified when considering long distance bus travel for clients. Practical considerations for travel preparation and education are provided. Additional research is needed examining the impact of specific aspects of long distance bus travel (e.g., smoking restrictions, number of transfers, and time duration and distance of travel) and the challenges and strengths associated with alternate modes of transportation (e.g., air and railway) for accessing social services.     

基于AS1773协议的突发同步设计

采用时分多址协议的光网络中, 突发同步是一项关键技术, 一般采用基于多相时钟的关键字检测法。基于对异步传输模式棗无源光网络的研究,提出了对AS1773协议的突发同步设计。采用了高速现场可编程门阵列的方式实现20 Mbps突发同步器,简化了电路的设计,相对于传统的专用集成电路设计方案设计方案,具有开发成本低、开发周期短的优点。     

通过二总线实现32及64点楼层显示探讨

以一个二总线应用实例,论述了现在的楼宇消防工程中通过二总线传送探头编号的方法及对接收数据进行处理,从而使楼宇显示器面板对火灾发生的具体位置进行显示及报警.     

Counterfactual reasoning,responsibility and blame for serial murders: the perception and prevention of violent crimes / Razonamiento contrafáctico,responsabilidad y culpa de los asesinatos en serie: la percepción y prevención de los crímenes violentos

The present research evaluates people’s perception of serial murders, analysing the effects of controllability in counterfactual reasoning about the past and the future, as well as attributions of responsibility and blame. Besides, the research analyses the effects of perspective (one’s own versus other people’s) in these attributions. Participants were 442 students who answered open-ended questions designed for this study. The first experiment shows that people focus on controllable factors previous to these events. When considering the avoidance and prevention of general serial murders, they focus on representatives of formal authority. Moreover, when judging from their own perspective, blame is attributed to the perpetrator and responsibility to both parties; while from another person´s perspective, they attribute feelings of either responsibility or guilt to the representatives of formal authority and a lack of these feelings to the perpetrator. The second experiment shows identical results regarding the specific case of a well-known serial killer in England and Spain. These findings demonstrate that this perception has implications for the legal framework and the prevention of violent crimes.