遗传支持向量机及其在人民币汇率变动方向预测中的应用

文文章基于金融时间序列的近期数据对未来的影响会大于早期数据,对应用于金融时间序列预测的支持向量机方法进行了改进,给出了不等权重支持向量机方法（USVM）及其多项式光滑化处理;将不等权重支持向量机方法应用于训练样本集的子集确定预测模型,给出了遗传不等权重支持向量机方法（GAUSVM）;对GAUSVM应用于汇率变动预测的实证分析发现,通过利用遗传算法对预测模型选优能够有效地提高USVM预测效果,加强其数据挖掘的功能。     

最小二乘支持向量机在条件异方差模型中的应用

相对于标准的支持向量机,最小二乘支持向量机是将求解二次规划问题转化为求解一组线性方程,从而能提高求解速度。将最小二乘支持向量机和GARCH模型相结合应用于金融时间序列预测中。通过在实际股票市场预测中的比较分析,能够证实所给方法是可行的、有效的。     

基于支持向量机回归的房地产单指标预测

对时间序列预测常用的方法进行了比较,结合房地产自身的特点确定用支持向量机回归来对房地产单项指标进行预测;分析了支持向量机回归和时序相空间重构的基本原理;建立了支持向量机预测模型,结合武汉市的实际数据进行了实证分析,并和BP神经网络的预测结果进行比较,表明用支持向量机预测模型进行房地产单项指标预测精度更高。     

在线预测的灰色支持向量回归方法

文章采取灰色系统和支持向量机相结合的方法,从预测精度和计算代价两方面讨论了经济时间序列数据的在线预测模式,提出了灰色自适应在线支持向量回归预测模型。两个经济时间序列的试验结果表明：该模型以稍高的计算代价能获得预测精度的明显提高,在选取合适灰色建模数据长度下,预测时间能迅速减少。     

基于支持向量机的降水量混沌时间序列预测

本文针对降水量时间序列的混沌性,根据混沌动力系统的相空间延迟坐标重构理论,基于支持向量机优越的非线性拟合性能,建立了基于支持向量机的降水量混沌时间序列预测模型。由于降水量时间序列的特殊性,本文采用均方根误差为标准来选取最优嵌入维数和模型参数,并结合实例验证该模型能精确地预测降水量。同时,这一结论也预示着支持向量机是一种研究混沌时间序列的有效方法。     

多变量混沌时间序列的最小二乘支持向量机预测

文章根据多变量混沌时间序列的相空间重构理论,建立了多变量时间序列的最小二乘支持向量机预测模型.通过Lorenz系统和中国股市的股票价格序列对该模型进行了验证,结果表明该预测模型能精确地预测混沌时间序列,并且优于基于单变量时间序列的最小二乘支持向量机预测模型.     

LS-SVM的一种参数优选方法及混沌时间序列预测

支持向量机是一种新型的学习方法,该方法以结构风险最小化原则取代传统机器学习中的经验风险最小化原则,在小样本的机器学习中显示出了优异的性能.文章提出适当的验证性能指标用遗传算法优化最小二乘支持向量机的有关参数,并进行时间序列预测.通过对混沌时间序列的预测及和神经网络预测的比较证明,该模型的预测精确度是令人满意的,文中提出的方法是可行的.     

金融时间序列混合智能预测模型及实证研究

文章针对金融时间序列变化复杂、难以用单一智能方法进行有效预测的问题,提出了一种新的基于经验模式分解、支持向量回归和粒子群优化的混合智能预测模型.经验模式分解能将非平稳时间序列按其内在的时间特征尺度自适应地分解为多个基本模式分量,根据这些分量各自趋势变化的剧烈程度选择不同的核函数进行支持向量回归预测,最后通过粒子群优化算法对各预测分量进行加权组合,得到原始序列的准确预测值.证券市场实证研究表明该模型可以准确预测金融时间序列.     

小波包与贝叶斯LS-SVM在石油价格预测中的应用

掌握国际石油价格变化趋势,可以为决策者提供决策依据.文章提出了基于小渡包和贝叶斯推断的最小二乘支持向量机石油价格预测方案.对石油价格时间序列进行小渡包分解与重构,采用贝叶斯推断对得到的各近似序列和各细节序列进行最小二乘支持向量机模型参数优化,再分别利用优化了的模型进行预测,合成得到最终预测结果.对美国纽约商品交易所原油价格进行仿真实验,结果表明该方法很好地改善了石油价格预测模型的运行速度与预测精度.     

基于双正交小波核支持向量机的长记忆汇率预测

对具有长记忆性的汇率数据进行准确预测具有重要的理论和现实意义。文章基于样条小波构造了一类新的双正交小波核函数并建立了相应的支持向量机模型。通过分数差分方法消除汇率数据的长记忆性,对欧元兑美元和欧元兑日元两个汇率数据进行了预测研究。结果表明双正交小波核支持向量机能够有效的避免过学习,其拟合优度和预测精度均优于正交小波核支持向量机和高斯核支持向量机。     

Automatic specification of piecewise linear additive models: application to forecasting natural gas demand

When facing any forecasting problem not only is accuracy on the predictions sought. Also, useful information about the underlying physics of the process and about the relevance of the forecasting variables is very much appreciated. In this paper, it is presented an automatic specification procedure for models that are based on additivity assumptions and piecewise linear regression. This procedure allows the analyst to gain insight about the problem by examining the automatically selected model, thus easily checking the validity of the forecast. Monte Carlo simulations have been run to ensure that the model selection procedure behaves correctly under weakly dependent data. Moreover, comparison over other well-known methodologies has been done to evaluate its accuracy performance, both in simulated data and in the context of short-term natural gas demand forecasting. Empirical results show that the accuracy of the proposed model is competitive against more complex methods such as neural networks.     

Statistical Issues in Weather Forecasting*

Research and operational applications in weather forecasting are reviewed, with emphasis on statistical issues. It is argued that the deterministic approach has dominated in weather forecasting, although weather forecasting is a probabilistic problem by nature. The reason has been the successful application of numerical weather prediction techniques over the 50 years since the introduction of computers. A gradual change towards utilization of more probabilistic methods has occurred over the last decade; in particular meteorological data assimilation, ensemble forecasting and post‐processing of model output have been influenced by ideas from statistics and control theory.     

我国季度GDP实时数据预测与评价

传统实证研究中使用的当期特定数据存在滞后信息和噪音信息缺陷,导致模型估计结果存在偏误。应用宏观经济实时数据可以有效的剔除造成模型偏误的滞后信息和噪音信息,得到更为准确的估计结果。MIDAS模型可将低频的关键经济数据与高频数据同时估计,较好的解决了应用一般模型存在的高频数据信息损失问题。本文应用M-MIDAS-DL模型与季度GDP实时数据建立我国季度GDP预测模型,实证表明,应用实时数据与组合预测方法,能及时准确预测出2008年以来中国经济增长率的下滑与反弹走势,能起到较好的提前预警作用,是当前较为有效的经济预测手段之一。     

Comparing Fits of Latent Trait and Latent Class Models Applied to Sparse Binary Data: An Illustration with Human Resource Management Data

This paper addresses the problem of comparing the fit of latent class and latent trait models when the indicators are binary and the contingency table is sparse. This problem is common in the analysis of data from large surveys, where many items are associated with an unobservable variable. A study of human resource data illustrates: (1) how the usual goodness-of-fit tests, model selection and cross-validation criteria can be inconclusive; (2) how model selection and evaluation procedures from time series and economic forecasting can be applied to extend residual analysis in this context.     

Forecasting With Bayesian Vector Autoregressions—Five Years of Experience

The results obtained in five years of forecasting with Bayesian vector autoregressions (BVAR's) demonstrate that this inexpensive, reproducible statistical technique is as accurate, on average, as those used by the best known commercial forecasting services. This article considers the problem of economic forecasting, the justification for the Bayesian approach, its implementation, and the performance of one small BVAR model over the past five years.     

Diffusion Indexes With Sparse Loadings

The use of large-dimensional factor models in forecasting has received much attention in the literature with the consensus being that improvements on forecasts can be achieved when comparing with standard models. However, recent contributions in the literature have demonstrated that care needs to be taken when choosing which variables to include in the model. A number of different approaches to determining these variables have been put forward. These are, however, often based on ad hoc procedures or abandon the underlying theoretical factor model. In this article, we will take a different approach to the problem by using the least absolute shrinkage and selection operator (LASSO) as a variable selection method to choose between the possible variables and thus obtain sparse loadings from which factors or diffusion indexes can be formed. This allows us to build a more parsimonious factor model that is better suited for forecasting compared to the traditional principal components (PC) approach. We provide an asymptotic analysis of the estimator and illustrate its merits empirically in a forecasting experiment based on U.S. macroeconomic data. Overall we find that compared to PC we obtain improvements in forecasting accuracy and thus find it to be an important alternative to PC. Supplementary materials for this article are available online.     

Forecasting the Incidence of Cancer in Regional Victoria,Australia

Loddon Mallee Integrated Cancer Service plays a key role in planning the delivery of cancer services in the Loddon Mallee Region of Victoria, Australia. Forecasting the incidence of cancer is an important part of planning for these services. This article is written from an industry perspective. We describe the context of our work, review the literature on forecasting the incidence of cancer, discuss contemporary approaches, describe our experience with forecasting models, and list issues associated with applying these models. An extensive bibliography illustrates the world-wide interest in this forecasting problem. We hope that it is useful to researchers.     

变权重组合预测模型的局部加权最小二乘解法

随着科学技术的不断进步，预测方法也得到了很大的发展，常见的预测方法就有数十种之多。而组合预测是将不同的预测方法组合起来，综合利用各个方法所提供的信息，其效果往往优于单一的预测方法，故得到了广泛的应用。而基于变系数模型的思想研究了组合预测模型，将变权重的求取转化为变系数模型中系数函数的估计问题，从而可以基于局部加权最小二乘方法求解，利用交叉证实法选取光滑参数。其结果表明所提方法预测精度很高，效果优于其他方法。     

灰色成分数据模型在中国产业结构分析预测中的应用

针对成分数据这种特殊类型的统计数据,提出一种新的预测建模方法:对于一列按照时间顺序收集的成分数据,先运用对数变换使成分数据降维,然后对降维后的数据运用GM(1,1)模型进行预测,最后再将预测值进行反对数变换,从而得到了各成分的预测值.根据提出的方法,建立了中国产业结构的预测模型,并分析了中国产业结构的发展趋势和未来状况.经检验,运用该方法预测出的数据与实际值十分吻合.