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61.
This article presents a new Qual VAR model for incorporating information from qualitative and/or discrete variables in vector autoregressions. With a Qual VAR, it is possible to create dynamic forecasts of the qualitative variable using standard VAR projections. Previous forecasting methods for qualitative variables, in contrast, produce only static forecasts. I apply the Qual VAR to forecasting the 2001 business recession out of sample and to analyzing the Romer and Romer narrative measure of monetary policy contractions as an endogenous variable in a VAR. Out of sample, the model predicts the timing of the 2001 recession quite well relative to the recession probabilities put forth at the time by professional forecasters. Qual VARs—which include information about the qualitative variable—can also enhance the quality of density forecasts of the other variables in the system.  相似文献   
62.
We address the problem of optimally forecasting a binary variable for a heterogeneous group of decision makers facing various (binary) decision problems that are tied together only by the unknown outcome. A typical example is a weather forecaster who needs to estimate the probability of rain tomorrow and then report it to the public. Given a conditional probability model for the outcome of interest (e.g., logit or probit), we introduce the idea of maximum welfare estimation and derive conditions under which traditional estimators, such as maximum likelihood or (nonlinear) least squares, are asymptotically socially optimal even when the underlying model is misspecified.  相似文献   
63.
Self-exciting threshold autoregressive moving average (SETARMA) nonlinear time-series model is considered here. Sufficient conditions for invertibility and stationarity are derived. Parameter estimation algorithm is developed by employing real-coded genetic algorithm stochastic optimization procedure. A significant feature of the work done is that optimal out-of-sample forecasts up to three-step ahead and their forecast error variances are derived analytically. Relevant computer programs are written in statistical analysis system (SAS) and C. As an illustration, annual mackerel catch time-series data are considered. Forecast performance of the fitted model for hold-out data is evaluated by using Naive and Monte Carlo approaches. It is found that optimal out-of-sample forecast values are quite close to actual values and estimated variances are quite close to theoretical values. Superiority of the SETARMA model over the SETAR model for equal predictive ability through Diebold–Mariano test is also established.  相似文献   
64.
Abstract

Recent work has emphasized the importance of evaluating estimates of a statistical functional (such as a conditional mean, quantile, or distribution) using a loss function that is consistent for the functional of interest, of which there is an infinite number. If forecasters all use correctly specified models free from estimation error, and if the information sets of competing forecasters are nested, then the ranking induced by a single consistent loss function is sufficient for the ranking by any consistent loss function. This article shows, via analytical results and realistic simulation-based analyses, that the presence of misspecified models, parameter estimation error, or nonnested information sets, leads generally to sensitivity to the choice of (consistent) loss function. Thus, rather than merely specifying the target functional, which narrows the set of relevant loss functions only to the class of loss functions consistent for that functional, forecast consumers or survey designers should specify the single specific loss function that will be used to evaluate forecasts. An application to survey forecasts of U.S. inflation illustrates the results.  相似文献   
65.
The process of serially dependent counts with deflation or inflation of zeros is commonly observed in many applications. This paper investigates the monitoring of such a process, the first-order zero-modified geometric integer-valued autoregressive process (ZMGINAR(1)). In particular, two control charts, the upper-sided and lower-sided CUSUM charts, are developed to detect the shifts in the mean process of the ZMGINAR(1). Both the average run length performance and the standard deviation of the run length performance of these two charts are investigated by using Markov chain approaches. Also, an extensive simulation is conducted to assess the effectiveness or performance of the charts, and the presented methods are applied to two sets of real data arising from a study on the drug use.  相似文献   
66.
全面建成小康社会,必须主动适应、把握、引领新常态。在对“小康社会”科学内涵研究的基础上,以国家统计局指标体系为基准,构建陕西省各地市全面建成小康社会进程指标体系,定量测算了2005-2014年间陕西省及其各地市的小康实现程度。结合陕西省新常态经济发展环境,预测陕西省各地市“十三五”期间的小康社会进程,预测结果显示陕西省小康社会总体呈稳步上升趋势;各区域差距较大,阶段性特征明显。因此,应通过进一步统筹区域发展,推进新型城镇化建设、实施创新驱动发展战略,同步够格地建成小康社会。  相似文献   
67.
简单平均组合预测有效性的应用分析   总被引:3,自引:0,他引:3  
通过实例分析,说明了当序列模式变动较大时,简单平均组合预测模型相对于其他组合预测模型的优越性,并且基于样本段的拟合精度不足以说明组合预测模型的外推预测精度。文中的分析对于组合预测模型的选择和应用具有实际参考价值。  相似文献   
68.
基于模糊逻辑系统的非线性组合预测方法研究   总被引:9,自引:1,他引:8  
针对线性组合预测方法的局限性,本文提出了一种基于高斯型模糊逻辑系统的非线性组合预测新方法,并给出了相应的反向传播学习算法确定模糊系统的参数及模糊子集的划分.理论分析和应用实例表明:该方法具有很强的学习与泛化能力,在处理诸如非线性系统中时间序列的组合建模与预测方面都良好的应用价值.  相似文献   
69.
借助PASW Statistics软件对2002年1月至2009年12月我国航空货运量月度数据序列进行分析,发现我国航空货运量的发展变化具有明显的上升趋势和季节性。通过构建航空货运量的ARIMA预测模型并进行检验,结果表明,ARIMA模型对原始数据序列有着较好的拟合效果,模型的预测误差较小,可应用于短期内我国航空货运量的预测,为进一步的航空货运市场调控提供有效依据。  相似文献   
70.
In the framework of competitive electricity market, prices forecasting has become a real challenge for all market participants. However, forecasting is a rather complex task since electricity prices involve many features comparably with those in financial markets. Electricity markets are more unpredictable than other commodities referred to as extreme volatile. Therefore, the choice of the forecasting model has become even more important. In this paper, a new hybrid model is proposed. This model exploits the feature and strength of the auto-regressive fractionally integrated moving average model as well as least-squares support vector machine model. The expected prediction combination takes advantage of each model's strength or unique capability. The proposed model is examined by using data from the Nordpool electricity market. Empirical results showed that the proposed method has the best prediction accuracy compared to other methods.  相似文献   
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