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1.
We consider the implications for forecast accuracy of imposing unit roots and cointegrating restrictions in linear systems of I(1) variables in levels, differences, and cointegrated combinations. Asymptotic formulae are obtained for multi-step forecast error variances for each representation. Alternative measures of forecast accuracy are discussed. Finite sample behaviour in a bivariate model is studied by Monte Carlo using control variables. We also analyse the interaction between unit roots and cointegrating restrictions and intercepts in the DGP. Some of the issues are illustrated with an empirical example of forecasting the demand for M1 in the UK.  相似文献   

2.
We present discrete time survival models of borrower default for credit cards that include behavioural data about credit card holders and macroeconomic conditions across the credit card lifetime. We find that dynamic models which include these behavioural and macroeconomic variables provide statistically significant improvements in model fit, which translate into better forecasts of default at both account and portfolio levels when applied to an out-of-sample data set. By simulating extreme economic conditions, we show how these models can be used to stress test credit card portfolios.  相似文献   

3.
This paper presents a forecasting model of bank failures based on machine-learning. The proposed methodology defines a linear decision boundary that separates the solvent banks from those that failed. This setup generates a novel alternative stress-testing tool. Our sample of 1443 U.S. banks includes all 481 banks that failed during the period 2007–2013. The set of explanatory variables is selected using a two-step feature selection procedure. The selected variables were then fed to a support vector machines forecasting model, through a training–testing learning process. The model exhibits a 99.22% overall forecasting accuracy and outperforms the well-established Ohlson’s score.  相似文献   

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In 1980, Palm and Zellner presented a number of joint or system estimation and testing procedures for the final equations, transfer functions and structural equations of a multivariate dynamic model with normally distributed vector moving average errors. In this paper, we show that there is a flaw in their argument which renders most of the procedures invalid. Possible alternative procedures are described.  相似文献   

5.
Joint two-step estimation procedures which have the same asymptotic properties as the maximum likelihood (ML) estimator are developed for the final equation, transfer function and structural form of a multivariate dynamic model with normally distributed vector-moving average errors. The ML estimator under fixed and known initial values is obtained by iterating the procedure until convergence. The asymptotic distribution of the two-step estimators is used to construct large sample testing procedures for the different forms of the model.  相似文献   

6.
The notion of cointegration has led to a renewed interest in the identification and estimation of structural relations among economic time series. This paper reviews the different approaches that have been put forward in the literature for identifying cointegrating relationships and imposing (possibly over-identifying) restrictions on them. Next, various algorithms to obtain (approximate) maximum likelihood estimates and likelihood ratio statistics are reviewed, with an emphasis on so-called switching algorithms. The implementation of these algorithms is discussed and illustrated using an empirical example.  相似文献   

7.
D M Rhyne 《Socio》1989,23(3):115-123
A comprehensive literature review of forecasting methodologies and their specific applications to managing hospital services demand provided a credible base for the ensuing study of current forecasting usage. A sample of 40 hospitals was analyzed to measure the current perceived urgency to utilize forecasting systems. These findings were then compared with perceived actual usage. The incidence of formal forecasting systems actually being utilized was lower than the perceived need to use such systems. Identification of principal methodologies utilized and an assessment of computer-assisted forecasting indicated that a strong reliance on qualitative, manually-derived methodologies still remains. Correlation analyses of key exogenous variables indicated that the larger sized hospitals utilized computerized methodologies and had the highest measures of perceived need for, and actual practice of, formal forecasting programs.  相似文献   

8.
This paper proposes a model for forecasting elections in Turkey. In doing so, this study is based on three theoretical premises: first, that the voters reward or punish parties according to their performances relative to the macroeconomic conditions; second, that the popularity of the political parties in Turkey are closely connected to their performances in local elections; and third, that the centre-periphery distinction affects the fortunes of the political parties in Turkey. The contribution of this analysis is the introduction of an explicit model on which can forecast the impact of economic and political variables on the elections in Turkey by using reliable, public and macro level data. Our findings show that the dynamics of the evaluation of political parties in Turkey follow a similar pattern to those of contemporary democracies, being driven by both economic and political factors.
“…why did AKP win? There cannot be a scientific and sociological explanation of this.”Özdemir ?nce, 17 August 2007, Hürriyet, emphasis added.
  相似文献   

9.
This paper considers two problems of interpreting forecasting competition error statistics. The first problem is concerned with the importance of linking the error measure (loss function) used in evaluating a forecasting model with the loss function used in estimating the model. It is argued that because the variety of uses of any single forecast, such matching is impractical. Secondly, there is little evidence that matching would have any impact on comparative forecast performance, however measured. As a consequence the results of forecasting competitions are not affected by this problem. The second problem is concerned with the interpreting performance, when evaluated through M(ean) S(quare) E(rror). The authors show that in the Makridakis Competition, good MSE performance is solely due to performance on a small number of the 1001 series, and arises because of the effects of scale. They conclude that comparisons of forecasting accuracy based on MSE are subject to major problems of interpretation.  相似文献   

10.
汪孔政 《基建优化》2007,28(3):103-104
提出采用组合模型预测建筑物沉降,并以常用的三种建筑物沉降预测模型组成组合模型进行了计算分析,结果表明组合预测模型具有较高的预测精度,值得推广应用.  相似文献   

11.
在线性回归与GM(1,1)组合模型对物流需求量预测,可取得优于单方法预测效果的前提下,将线性回归法运用到与DGM(1,1)模型进行组合,检测该组合灰色预测模型对物流需求量预测效果。通过对国内2001-2012年物流需求量历史数据的分析,发现组合灰色预测模型的预测效果优于线性回归模型,但低于DGM(1,1)模型,最后利用线性回归模型、DGM(1,1)模型、简单平均组合模型和组合灰色预测模型对国内2013-2017的物流需求量进行了有效预测。  相似文献   

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针对灰色预测模型在区域物流中不能有效解决因季节变动而引起的物流需求变化的问题,引入季节指数的概念,构建基于灰色模型和季节指数的物流需求预测模型,并给出了相应的具体实施方案.最后以哈尔滨市物流需求统计数据为例,对所提方法进行了仿真分析,仿真结果表明了该方法的有效性和可行性.  相似文献   

14.
蒋惠园  张安顺 《物流技术》2020,(2):44-47,140
为使港口集装箱吞吐量预测的误差更小,精度更高,提出运用弹性系数法、灰色模型法、三次指数平滑法的组合预测模型,预测了武汉港未来特征年的集装箱吞吐量,研究结果表明,组合模型相比单一预测方法能够降低误差、提高精度,预测结果更加理想。  相似文献   

15.
刘莉 《物流技术》2010,29(8):41-42,46
针对灰色预测模型在区域物流中不能有效解决因季节变动而引起的物流需求变化的问题,引入季节指数的概念,构建基于灰色模型和季节指数的物流需求预测模型,并给出了相应的具体实施方案。最后以哈尔滨市物流需求统计数据为例,对所提方法进行了仿真分析,仿真结果表明了该方法的有效性和可行性。  相似文献   

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This Briefing Paper is thejirst ofa series of three designeddiscussed is the process of making 'constant adjustments' in forecasts. This process involves modifying the results generated by the econometric model. For the first time we are publishing tables of the constant adjustments used in the current forecast. We explain in general why such adjustments are made and also explain the actual adjustments we have made for this forecast.
The second article of the series, to be published in our February 1983 edition, will describe the potential sources of error in forecasts. In particular it will describe the inevitable stochastic or random element involved in e tatistical attempts to quantify economic behaviour. As a completely new departure the article will report estimates of future errors based on stochastic simulations of the LBS. model and will provide statistical error bad for the main elements of the forecast.
The final article, to be published in our June 1983 edition, will contrast the measures of forecast error that e e obtain from the estimation process and our stochastic e imulationsp with the errors that we have actually made, as revealed by an examination of our forecasting 'track record'. It is hoped to draw, from this comparison, some e eneral conclusions about the scope and limits of econometric forecasting producers.  相似文献   

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