Do Leading Indicators Lead Peaks More Than Troughs?

We develop a novel Markov switching vector autoregressive model to investigate the possibility that leading indicators have different lead times at business cycle peaks and at troughs. In this model, coincident and leading indicators share a common Markov state process, but their cycles are nonsynchronous, with the nonsynchronicity varying across regimes. An application shows that on average the Conference Board’s Composite Leading Index leads the Composite Coincident Index by nearly 1 year at peaks but by only 1 quarter at troughs. Allowing for asymmetric lead times yields improved real-time dating and forecasting of business cycle turning points.     

Normalization rules for item response models: Simulation results

ABSTRACT

This research examines the statistical methodology that is used to estimate the parameters in item response models. An integral part of an item response model is the normalization rule that is used to identify the distributional parameters. The main result shown here is that only Verhelst–Glas normalizations that arbitrarily set one difficulty and one dispersion parameter to unity are consistent with the basic assumptions underlying the two-parameter logistic model. Failure to employ this type of normalization will lead to scores that depend on the item composition of the test and differential item difficulty (DIF) will compromise the validity of the estimated ability scores when different groups are being compared. It is also shown that some of the tests for DIF fail when the data are generated by an IRT model with a random effect. Most of the results are based on simulations of a four item model. Because the data generation mechanism is known, it is possible to determine the effect on ability scores and parameter estimates when different normalizations or different distribution parameter values are used.     

Bayesian Mixture Labeling and Clustering

Label switching is one of the fundamental issues for Bayesian mixture modeling. It occurs due to the nonidentifiability of the components under symmetric priors. Without solving the label switching, the ergodic averages of component specific quantities will be identical and thus useless for inference relating to individual components, such as the posterior means, predictive component densities, and marginal classification probabilities. The author establishes the equivalence between the labeling and clustering and proposes two simple clustering criteria to solve the label switching. The first method can be considered as an extension of K-means clustering. The second method is to find the labels by minimizing the volume of labeled samples and this method is invariant to the scale transformation of the parameters. Using a simulation example and the application of two real data sets, the author demonstrates the success of these new methods in dealing with the label switching problem.     

A Study on EWMA charts with runs rules—the Markov chain approach

ABSTRACT

Runs rules are usually used with Shewhart-type charts to enhance the charts' sensitivities toward small and moderate shifts. Abbas et al. in 2011 took it a step further by proposing two runs rules schemes, applied to the exponentially weighted moving average (EWMA) chart and evaluated their average run length (ARL) performances using simulation. They showed that the proposed schemes are superior to the classical EWMA chart and other schemes being investigated. Besides pointing out some erroneous ARL and standard deviation of the run length (SDRL) computations in Abbas et al., this paper presents a Markov chain approach for computing the ARL, percentiles of the run length (RL) distribution and SDRL, for the two runs rules schemes of Abbas et al. Using Markov chain, we also propose two combined runs rules EWMA schemes to quicken the two schemes of Abbas et al. in responding to large shifts. The runs rules (basic and combined rules) EWMA schemes will be compared with some existing control charting methods, where the former charts are shown to prevail.     

Prbposterior expected loss as a scoring rule for prior distributions

A scoring rule for evaluating the usefulness of an assessed prior distribution should reflect the purpose for which the distribution is to be used. In this paper we suppose that sample data is to become available and that the posterior distribution will be used to estimate some quantity under a quadratic loss function. The utility of a prior distribution is consequently determined by its preposterior expected quadratic loss. It is shown that this loss function has properties desirable in a scoring rule and formulae are derived for calculating the scores it gives in some common problems. Many scoring rules give a very poor score to any improper prior distribution but, in contrast, the scoring rule proposed here provides a meaningful measure for comparing the usefulness of assessed prior distributions and non-informative (improper) prior distributions. Results for making this comparison in various situations are also given.     

基于心理契约视角的“文化建设”管理问题研究

以“心理契约”理论为基础,结合中共十七大、十八大报告“文化建设’’战略有关论述,系统阐述了“文化建设”管理目标是构建以“物质心理契约”、“制度心理契约”、“行为心理契约”和“精神和价值观心理契约”为表达形式的“民族共同心理契约”。“文化建设”管理最佳目标模式选择是“有意识规范管理模式”,“文化建设”管理规律是按照文化生命周期规律推动文化的不断丰富、创新和发展等若干理论和实践问题。     

我们为什么一定要“信仰广告”？——新世纪中国社会消费生活信仰现象分析

进入21世纪的头一个10年,中国人的生活方式发生了较为明显的变化。一方面是＂消费生活＂开始成为主导;一方面是＂温饱生活＂逐步淡出。伴随生活的变化,我们对生活的理解也开始了变化。在这种变化中,主张消费生活,享受消费生活,成中国人的现代生活宗教。而我们的消费生活宗教信仰,是由＂信仰广告＂来引领和确证的。信仰广告已经成为今天中国人消费生活信仰的＂历史导向＂（华丽外衣）。中国人在现代消费生活里所以信仰广告,不仅与人类对传播的＂本质信仰＂相关,也与我们市场的＂高度繁荣＂和＂过度竞争＂有关。要想在丰富度和竞争度极高的市场中不迷失方向,信赖和信仰广告,是我们惟一的选择。     

国际投资仲裁透明度改革及我国的应对

近年来,基于条约提起的国际投资争议仲裁的秘密性所暴露的缺陷备受关注,对此,不少学者倡导在仲裁机制内提高程序透明度,以补苴罅漏。一些仲裁规则和国际投资条约也已经就该问题做了相关规定或修改,将透明度要求推进到了改革实践阶段。就目前而言,对这场改革的功效进行褒贬时机尚早,且不能执一而论。然而,透明度改革作为一项重大变化,无疑会对国际投资仲裁的未来发展路径产生影响,其所承载的价值取向也反映了国际法治和文明的发展方向,因此,对其原则性的规定我国应予以支持。同时,我国作为兼具资本输出国和输入国双重身份的大国,应正视投资仲裁透明度改革可能带来的蝴蝶效应,谨慎考虑国内法治面临的挑战。对此,我国应从规范文本及文本之外的其他领域两个层面分别采取措施,予以应对。     

论南京国民政府时期的土地所有权

南京国民政府＂六法全书＂的颁布,标志着现代法律体系移植的完备。就成文法体系而言,一方面民国民法典和民国土地法确立了完善的土地所有权体系;另一方面民国立法者以个人所有权取代家产制,以民法公同共有和永佃权的法理对祭田、＂一田二主＂习惯进行改造。从司法层面来看,法官们应在充分尊重固有地权交易习惯基础上,以西方民事法理去充分说理。