基于二重趋势预测模型的安徽城市居民消费价格总指数预测分析

主要针对安徽城市居民消费价格指数的变化进行研究,重点分析了消费价格总指数的增加趋势和周期循环态势,预测未来几年安徽城市居民消费价格指数将在增加趋势和周期循环趋势的共同作用下出现的态势,分析其具体的原因并提出双向控制、承接大势、农村先行和稳定房价等建议。     

通辽市水稻生产资源分析及前景预测

本文系统地分析了影响水稻生产发展的气侯、土地、水资源和社会因素等．从产量变化、气候变化、经济效益的角度预测了通辽市水稻生产的发展前景．     

刘文典与新文化运动时期的鬼神观

在中国社会急速转型的民国时期,民众精神思想极度贫乏,因而封建鬼神的唯心主义思潮进入大众视野。刘文典用文章对封建的鬼神观进行严厉批判,同时引进了一些西方先进的哲学理念。他深信观念的改变对于一个人乃至一个国家都具有重要作用,主张从西学的角度来改变国人的精神面貌。     

Health-Based Population Forecasting: Effects of Smoking on Mortality and Fertility

A microsimulation model, allowing one to forecast short- and long-term population changes conditional on the prevalence of a risk factor in a population, is presented. In this model, population changes result from the aggregation of changes in individual event histories, which, in turn, result from mortality and infertility rates recalculated in accordance with their known relative risks in population groups exposed to a risk factor. Smoking, being the most widespread and influential preventable public health risk factor, is chosen to demonstrate the abilities of the model to forecast the population effects of different hypothetical smoking prevalences. The demographic and population health effects on 20-, 50-, and 100-year projections with the current, hypothetically doubled, and hypothetically halved the current smoking prevalence are analyzed in detail. The model predicts an increase in life expectancy (0.99 year for males and 0.64 years for females), and an increase in population size (2.2-7.5% dependent on the age group) if smoking prevalence is reduced by half. Sensitivity analyses of all findings are performed. The generalization of the model to account for multiple risk factors (e.g., the simultaneous effects of alcohol consumption, obesity, and smoking) and effects on medical expenditures are discussed.     

Exit polling in a cold climate: the BBC–ITV experience in Britain in 2005

Summary.  Conducting an exit poll to forecast the outcome of a national election in terms of both votes and seats is particularly difficult in Britain. No official information is available on how individual polling stations voted in the past, use of single-member plurality means that there is no consistent relationship between votes and seats, electors can choose to vote by post and most of those who vote in person do so late in the day. In addition, around one in every six intended exit poll respondents refuses to participate. Methods that were developed to overcome these problems, and their use in the successful 2005 British Broadcasting Corporation–Independent Television exit poll, are described and evaluated. The methodology included a panel design to allow the estimation of electoral change at local level, coherent multiple-regression modelling of multiparty electoral change to capture systematic patterns of variation, probabilistic prediction of constituency winners to account for uncertainty in projected constituency level shares, collection of information about the voting intentions of postal voters before polling day and access to interviewer guesses on the voting behaviour of refusals. The coverage and accuracy of the exit poll data are critically examined, the effect of key aspects of the statistical modelling of the data is assessed and some general lessons are drawn for the design and analysis of electoral exit polls.     

赛莱菲耶思潮探微

伊斯兰教历史上，赛莱菲耶思潮最早是在阿拔斯王朝时期掀起的。公元13世纪，伊本·泰米叶及其弟子伊本·嘎伊姆成为这一思潮的旗手。赛莱菲耶思潮反对凯拉姆学所展开的教义学争辩，呼吁回93原生态伊斯兰和《古兰经》。与此同时，伊本·泰米叶还率先对“创制之门关闭”说提出质疑，从而证明赛莱菲耶思潮所倡导的“循古”并不是教条和僵化的。尤其是伊本·嘎伊姆提出的注重“现实”和在此基础上的合理创制，更不无合理成分。     

Understanding the Kalman Filter

This is an expository article. Here we show how the successfully used Kalman filter, popular with control engineers and other scientists, can be easily understood by statisticians if we use a Bayesian formulation and some well-known results in multivariate statistics. We also give a simple example illustrating the use of the Kalman filter for quality control work.     

我国未来中长期劳动力需求预测

本文结合经济预测,对我国未来中长期2010-2050年劳动力需求进行了定量预测。预测结果表明,随着经济增长方式的转变、劳动生产率的提高,我国未来劳动力需求有下降的趋势,但下降比较缓慢,而我国劳动力供给量在＂十二五＂期间达到顶峰后会迅速下降,2016年后我国劳动力市场将可能长期面临劳动力短缺问题。     

A Cross-Validation Analysis of Neural Network Out-of-Sample Performance in Exchange Rate Forecasting

Econometric methods used in foreign exchange rate forecasting have produced inferior out-of-sample results compared to a random walk model. Applications of neural networks have shown mixed findings. In this paper, we investigate the potentials of neural network models by employing two cross-validation schemes. The effects of different in-sample time periods and sample sizes are examined. Out-of-sample performance evaluated with four criteria across three forecasting horizons shows that neural networks are a more robust forecasting method than the random walk model. Moreover, neural network predictions are quite accurate even when the sample size is relatively small.     

Predicting recessions using trends in the yield spread

The yield spread, measured as the difference between long- and short-term interest rates, is widely regarded as one of the strongest predictors of economic recessions. In this paper, we propose an enhanced recession prediction model that incorporates trends in the value of the yield spread. We expect our model to generate stronger recession signals because a steadily declining value of the yield spread typically indicates growing pessimism associated with the reduced future business activity. We capture trends in the yield spread by considering both the level of the yield spread at a lag of 12 months as well as its value at each of the previous two quarters leading up to the forecast origin, and we evaluate its predictive abilities using both logit and artificial neural network models. Our results indicate that models incorporating information from the time series of the yield spread correctly predict future recession periods much better than models only considering the spread value as of the forecast origin. Furthermore, the results are strongest for our artificial neural network model and logistic regression model that includes interaction terms, which we confirm using both a blocked cross-validation technique as well as an expanding estimation window approach.