The real exchange rate,fiscal policy and the role of wealth an analysis of equilibrium in a monetary union

This paper is concerned with the adjustment processes within a potential European monetary union and looks in particular at permanent asymmetric shocks that require an adjustment in a country's (or region's) real exchange rate. We first consider some of the implications of EMU and the question of asymmetries within the European economy. The presence of asymmetries and, in particular, different institutional structures in labour markets is a potential source of tension within a union and it could make a union difficult to sustain. However, automatic adjustment processes will be at work within a monetary union as a result of changes in relative price levels, which change real exchange rates, and also as a result of changes in wealth stocks. We use our econometric world model, NIGEM, to investigate the effects of asymmetric fiscal expansions and real exchange rate misalignments within a monetary union. In order to quantify the effects of such permanent asymmetric shocks we have introduced wealth into our model. Our simulations suggest that the principal impact of the fiscal expansion on both output and the price level will occur within the country in which the expansion occurs. Short-term gains are crowded out in the medium term, and while monetary union reduces crowding out in the short term, it increases the rate at which crowding out occurs thereafter. We also analyse the effects of real exchange rate misalignments and find that the processes of adjustment may be very protracted. This could cause strain on the union as adjustment costs are shared unequally.     

Forecast comparisons of four models of U.S. interest rates

In this paper we compare the out of sample forecasts from four alternative interest rate models based on expanding information sets. The random walk model is the most restrictive. The univariate time series model allows for a richer dynamic pattern and more conditioning information on own rates. The multivariate time series model permits a flexible dynamic pattern with own- and cross-series information. Finally, the forecasts from the MPS econometric model depend on the full model structure and information set. In theory, more information is preferred to less. In practice, complicated misspecified models can perform much worse than simple (also probably misspecified) models. For forecasts evaluated over the volatile 1970s the multivariate time series model forecasts are considerably better than those from simpler models which use less conditioning information, as well as forecasts from the MPS model which uses substantially more conditioning information but also imposes ‘structural’ economic restrictions.     

水溶性壳聚糖的热分解动力学研究

利用多重扫描速率法研究了商品水溶性壳聚糖(盐酸盐)的热分解反应动力学.主分解过程可以分为两个阶段,首先是高分子盐的分解,其次是高分子链的解聚合,两个阶段的反应活化能E和指前因子lnA值分别为173.99±2.63,128.97±1.87 kJ·mol-1和35.28±0.62,24.69±0.44 min-1.利用Achar微分法判定该物质两个阶段的热分解最概然机理函数相同,为f(α)＝ 1-α,该模型属于每个颗粒上只有一个核心的随机成核和随后生长机理.     

基于RF的无线传感器网络的MAC协议设计

针对传统无线传感器网络能量供应问题,提出了基于射频能量捕获的无线传感器网络介质访问控制（medium access control,MAC）协议。首先在相邻节点之间运用时分多址（time division multiple access,TDMA）技术按时隙分配信道,使数据在源节点到汇聚节点之间无争用传输;同时控制节点在每个周期内消耗的能量,间接调整节点自身的占空比;然后在缓冲区中设置负载阈值作为节点在通信转换角色中的依据,实现节点间的时间同步;最后对各种网络拓扑结构进行实验模拟,评估其延迟率和数据丢包率。实验结果表明：该协议与基于自适应时分多址的介质访问控制（adaptive TDMA-based MAC,AT-MAC）协议相比,不但延迟率低而且网络模拟结构更接近于现实网络场景,可以满足无线传感器网络的性能需求。     

动水条件下泥沙絮凝体粒径变化分析实验研究

絮凝体广泛存在于自然界水体中,而在河口海岸动水环境下的黏性细颗粒泥沙的絮凝变化过程是一个重要且有待完善的研究课题。利用长江口北槽现场悬沙样本开展了系统的室内絮凝实验。采用粒径分布与有效粒径两种分析方法,研究了在水流紊动、盐度和悬沙浓度等不同絮凝因子条件作用下对长江口北槽泥沙絮凝体粒径变化的影响。实验结果表明:紊动剪切率对絮凝体粒径作用为先促进后减小,临界值出现在23. 09 s~(-1),此时最大有效粒径为50. 26μm;而悬沙浓度会抑制絮凝体生长;同时长江口北槽悬沙的絮凝饱和盐度要大于高岭土,约为14. 4 ppt。     

Forecasting Longevity Gains Using a Seemingly Unrelated Time Series Model

In this paper a multivariate time series model using the seemingly unrelated time series equation (SUTSE) framework is proposed to forecast longevity gains. The proposed model is represented in state space form and uses Kalman filtering to estimate the unobservable components and fixed parameters. We apply the model both to male mortality rates in Portugal and the USA. Our results compare favorably, in terms of mean absolute percentage error, in‐sample and out‐of‐sample, to those obtained by the Lee–Carter method and some of its extensions. Copyright © 2015 John Wiley & Sons, Ltd.     

Predicting exchange rates in Asia: New insights on the accuracy of survey forecasts

By linking measures of forecast accuracy as well as testing procedures with regard to forecast rationality this paper investigates aggregated survey forecasts with forecast horizons of 3, 12, and 24 months for the exchange rates of the Chinese yuan, the Hong Kong dollar, the Japanese yen, and the Singapore dollar vis-à-vis the US dollar and, hence, for four different currency regimes. The rationality of the exchange rate predictions is initially assessed utilizing tests for unbiasedness and efficiency which indicate that the investigated forecasts are irrational in the sense that the predictions are biased. As one major contribution of this paper, it is subsequently shown that these results are not consistent with an alternative, less restrictive, measure of rationality. Investigating the order of integration of the time series as well as cointegrating relationships, this empirical evidence supports the conclusion that the majority of forecasts are in fact rational. Regarding forerunning properties of the predictions, the results are rather mediocre, with shorter term forecasts for the tightly managed USD/CNY FX regime being one exception. As one additional important and novel evaluation result, it can be concluded, that the currency regime matters for the quality of exchange rate forecasts.     

汇率与公司利润

汇率的一个重要职能就是价格转换功能,它是形成各种相对价格的基础。汇率变化会通过相对价格的变化而对一个国家的贸易收支状况和公司的价值,利润及其它的财务指标产生较大的影响。本文将探讨汇率变化对进出口企业利润产生的影响。在假定生产厂商追求利润最大化目标的前提下,作者得出了如下的结果：１）对于纯出口型企业,公司利润对汇率的弹性为国外对公司出口产品的需求弹性;２）对于纯进口型企业,公司利润对汇率的弹性为公司进口产品的需求弹性;３）对于进出口型企业,公司利润对汇率的弹性为０,即汇率变化对该类公司利润不产生影响。最后,作者提供了测算进,出口企业利润对汇率弹性的一般方法。     

论自杀的道德合理性

关于自杀,引起了很多伦理学上的讨论,其中最基本的是关于自杀的道德合理性问题,普遍认为个体对他人的义务是限制自杀合理性的主要因素。其中一种反对观点认为,将自杀看作一种权利的观点并没有很好地解决自杀的道德许可性问题;另一种反对观点则认为自杀是一个纯粹的私人问题,所以对他人的义务不能成为限制自杀的理由。然而,无论从利他因素考虑还是从利己因素考虑,在特定条件下自杀是可以被允许的,自杀的合理性可以得到辩护。     

揭开减人而不是减工之谜──兼谈国企富余职工“下岗分流”

本文提出了衡量企业劳动力是否富余的标准,分析了隐性失业的成困,揭示了存在隐性失业时企业为什么要减人而不是减少每人工时并按比例减少工资的意义,最后阐明了裁减企业富余职工达到预期成效应具备的一些条件．