Composite model building for foreign exchange rates

It has been shown in recent economic and statistical studies that composite forecasts may produce more accurate forecasts than individual ones. The purpose of this study is to develop composite forecasting models that may produce forecasts superior to the individual forecast implicit in forward exchange rates. In an efficient market one would expect to find little improvement with the composite models relative to the forward exchange rate.     

Forecasting interest rate swap spreads using domestic and international risk factors: evidence from linear and non‐linear models

This paper explores the ability of factor models to predict the dynamics of US and UK interest rate swap spreads within a linear and a non‐linear framework. We reject linearity for the US and UK swap spreads in favour of a regime‐switching smooth transition vector autoregressive (STVAR) model, where the switching between regimes is controlled by the slope of the US term structure of interest rates. We compare the ability of the STVAR model to predict swap spreads with that of a non‐linear nearest‐neighbours model as well as that of linear AR and VAR models. We find some evidence that the non‐linear models predict better than the linear ones. At short horizons, the nearest‐neighbours (NN) model predicts better than the STVAR model US swap spreads in periods of increasing risk conditions and UK swap spreads in periods of decreasing risk conditions. At long horizons, the STVAR model increases its forecasting ability over the linear models, whereas the NN model does not outperform the rest of the models. Copyright © 2007 John Wiley & Sons, Ltd.     

论自信的养成

自信是现代社会对人才素质的基本要求,自信是个体成长、成熟、成才、成功的重要心理品质.自信的养成途径有:展示优势,充分挖掘潜能;悦纳劣势,主动克服或补偿;积极地自我暗示;坦然地接受失败并尝试改变;别在乎别人的评价;确立恰当的目标;培养乐观幽默的个性.     

弹头侵彻高强装甲钢运动规律及弹坑周围塑性切应变分布

探讨弹头侵彻３０ＭｎＣｒＮｉＭｏＢ高强装甲钢的运动规律，确定弹甲相互作用时间（τ），结果表明τ与弹头初速度无关．借助该钢基体内具有的带状组织测量弹坑周围材料塑性切应变呈山峦起伏分布，并给出塑性变形的应变速率（１０４ｓ－１）以及ＡＳＢ形成的应变速率（１０５ｓ－１）．     

考虑红利支付的最优消费投资模型研究

研究了金融市场上证券投资的随机模型。证券价格的波动行为用随机微分方程加以刻划。考虑红利支付过程后，探讨了投资商的最优消费与投资的一般特征。并就模型系数为常系数情形导出反馈形式的最优消费与投资公式。     

南极长城站地区企鹅的种群数量与分布

１９９３－１１－１９９４－０３对南极长城站地区的企鹅种群的数量和分布进行了调查，共记录到６种企鹅即阿德利企鹅巴布亚全鹅，南级企鹅，长冠企鹅，王企鹅和帝企鹅。其中前３种企鹅在本地区繁殖，后３种企鹅为本地区鸟类分布的新记录。在长城站地区繁殖的企鹅总数约为１．１万只，繁殖成功率为１．３０－１．５７只／对。     

2D大U Hubbard模型核自旋驰豫研究

本文从Spinon与2D格点上Cu~( )离子的自旋耦合作用出发,讨论CuO_2平面的2DHubbard模形的自旋格点驰豫率1/T_1。理论计算的结果与氧化物高温超导材料的1/T_1实验结果比较,说明可以用S波超流理论解释实验现象。     

Breeding behaviour and mating success of Phyllomedusa rohdei (Anura,Hylidae) in south‐eastern Brazil

Observations on the courtship behaviour, mating behaviour and mating success of a leaf‐frog, Phyllomedusa rohdei, population were conducted in a temporary flooded site of the Atlantic Forest, south‐eastern Brazil. We did not find any influence of size and body weight on male mating success across three scales: seasonal, nightly chorus and local groups (males found within 1?m of a mated pair). In addition, no evidence was found that female Phyllomedusa rohdei exhibit overt mate choice. The formation of mated pairs in P. rohdei occurred because males moved toward the females, rather than reverse. The only variable that was significantly related to male mating success was the number of nights of participation in chorus activity. Besides calling tactics, males showed active searching behaviour. There was no evidence of size‐ and mass‐assortative mating, and a high percentage of fertilization at all size and mass ratios of males and females was observed. Clutches in this species are produced in the same manner found in others members of Phyllomedusa; a purse‐like nest is made over water by folding a leaf around the egg mass (embryos and fluid‐filled capsules). Finally, we supply a list of several studies that examined the relationship between size or mass ratios of males and females in amplexus and its influence on fertilization rate, and show that size‐assortative mating in anurans is inconsistent (present in some species but not in other).     

Twisting the Dollar? On the Consistency of Short‐Run and Long‐Run Exchange Rate Expectations

We examine consistency properties of the exchange rate expectation formation process of short‐run and long‐run forecasts in the dollar/euro and yen/dollar market. Applying nonlinear consistency restrictions we show that in a simple expectation formation structure short‐run forecasts are indeed inconsistent with long‐run predictions. Moreover, we establish a ‘twist’ in the dollar/euro expectation formation process, i.e. market participants expect bandwagon effects in the short run, while they have stabilizing expectations in their long‐run forecasts. Applying a panel probit analysis we find that this twisting behavior is more likely to occur in periods of excess exchange rate volatility. Copyright © 2011 John Wiley & Sons, Ltd.     

试论张尔岐的《仪礼》诠释特色及其成就

在清初礼学的复兴运动中,张尔岐所著《仪礼郑注句读》在对《仪礼》的整体把握乃至局部礼仪的研究、治礼方法的探索等方面,都具有自身的独到认知和特色,创见良多。将张尔岐的《仪礼》诠释置身于清初礼经诠释史的背景下进行观照,发掘万氏礼经研习的学术取向、注释体例和诠释特色,以及礼经诠释的校勘、辨伪情况,不仅有助于认知张尔岐礼经学的实际价值和贡献,更有助于重构与还原清代礼学研究的真实面貌。