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1.
分析了灰色系统预测模型GM(1,1)对高增长指数序列建模适应性较差的原因,通过重构背景值计算公式,建立了一个适应性极强的灰色系统预测模型NGM(1,1),该模型具有对建模结果进行优化的能力.算例结果表明该模型对低增长指数序列和高增长指数序列建模都能获得最佳的拟合和预测精度,对经济、工程和自动控制等领域中的预测问题有较高的理论价值和实践意义.  相似文献   

2.
为了提高GM(1,1)模型对随机振荡序列的拟合和预测效果,提出了先将原始振荡序列变为单调增长序列,再对单调增长序列进行几何平均生成交换,然后建立GM(1,1)模型.通过实例计算表明,方法能够提高GM(1,1)模型的拟合精度,可以用于随机振荡序列的建模,从而扩大了GM(1,1)模型的应用范围.  相似文献   

3.
GM(1,1)模型预测精度仿真分析   总被引:1,自引:0,他引:1  
基于GM(1,1)模型的灰色预测具有独特优点.从GM(1,1)建模数据的选择入手,应用数值仿真方法,针对具有不同发展系数和偏离度的大量模拟序列研究了建模维数与预测精度之间的关系.研究结果给出了不同情况下的最佳建模维数和预测精度期望值,为GM(1,1)建模提供了有益的指导信息.  相似文献   

4.
道路交通事故预测是道路交通安全研究的一项重要内容,针对灰色GM(1,1)预测模型对波动性较大道路交通事故序列预测精度较低的缺点,引入小波分析理论,在小波分析理论的基础上建立灰色GM(1,1)预测模型.通过小波分析将某省2002-2009年道路交通事故起数分解成多层近似平稳的数据序列,然后对低频重构序列建立GM(1,1)模型进行预测.仿真结果表明,方法的预测结果比直接用灰色GM(1,1)模型更拟合原始数据,预测效果更好.预测结果可以为交通部门科学监管和制定决策提供一定的指导.  相似文献   

5.
灰色时序组合模型及其在地下水埋深预测中的应用   总被引:1,自引:0,他引:1  
地下水埋深的变化过程是一个复杂的非线性过程,这种具有复杂的非线性组合特征的序列,使用某一种模型进行预测,结果往往不理想.在分析了灰色GM(1,1)模型、灰色GM(1,1)周期性修正模型和时序AR(n)模型的优点和缺点基础上,提出了一种新的灰色时序组合预报模型.该方法利用了GM预测所需原始数据少、方法简单的优点,用周期修正方法反映其地下水位埋深周期性波动的特征,用AR(n)模型预报其地下水位埋深的随机变化.实例研究表明,这种方法方便简洁实用且预测结果接近于实际观测值,为其它地区的地下水位埋深和相关时间序列的分析研究提供参考与借鉴作用.  相似文献   

6.
准确预测油田产量对油田开发调整部署有重要意义.依据油田产量变化特征与油田产量数据丰富的特点,引入产量变化系数修正传统灰色模型,并运用中心差商改进了传统灰导数离散过程,减小灰导数离散误差,再结合PSO算法,最终建立了PSO-改进GM(1,1)模型.运用PSO-改进GM(1,1)模型进行油田产量预测,对比传统灰色模型与PSO-改进GM(1,1)模型的产量预测结果可知,与传统灰色模型预测结果相比,应用PSO-改进GM(1,1)模型进行油田产量预测具有更高的准确性.  相似文献   

7.
针对GM(1,1)幂模型对于小样本振荡序列对含突变信息无能为力的问题,提出了基于小波变换的小样本振荡序列灰色预测模型.首先,针对原始数据序列建立GM(1,1)幂模型描述其总体趋势特征;然后,利用小波变换提取GM(1,1)幂模型残差序列所包含的有用信号和随机噪声,并结合GM(1,1)幂模型构成新的时间相应函数;最后,以与原始平均误差最小为原则确定小波变换的小波基和分解层次并对小波进行重构GM(1,1)幂模型残差序列,并结合原始GM(1,1)幂模型对随机振荡序列进行预测.算例中通过对城市用水量的拟合及预测结果表明:应用基于傅立叶变换的GM(1,1)幂振荡序列模型和基于分数阶离散GM(1,1)幂模型研究了振荡序列模型平均误差分别为3.22%和5.66%,而本文的方法平均误差为1.11%.算例研究表明,此方法能够快速高效的解决GM(1,1)幂模型对小样本有突变趋势振荡序列的预测问题.  相似文献   

8.
针对GM(1,1)模型对上凸序列建模时会出现误差较大的情况进行了研究.首先分析了GM(1,1)对上凸序列建模时的残差变化规律,然后通过分析得出了残差变化规律的精确描述,同时证明了残差序列的几个性质定理.基于残差序列的性质定理提出了基于上凸序列建模的残差修正GM(1,1)模型.将新模型与多种改进的GM(1,1)模型进行对比,实证结果表明新模型具有很高的模拟预测精度,并且适用于一切上凸序列的建模.  相似文献   

9.
本文以灰色系统理论的GM(1,1)模型和随机过程理论的Markov链模型为基础构建了一个动态GM(1,1)-Markov链组合预测模型。该模型同时利用了GM(1,1)模型对序列趋势因素良好的拟合能力和Markov链模型对残差序列信息的提取能力。为进一步提高该模型的预测精度,用泰勒(Taylor)近似方法和新信息优先的思想对该模型进行了改进。最后,以1991-2014年广东省单位GDP能耗数据实证了该模型的预测效果。  相似文献   

10.
针对GM(1,1)模型未能反映系统时滞效应的问题,根据实际应用的需要,利用灰色建模思想构建了含时滞参数7的灰色GM(1,1,Υ)模型,并研究了该模型的建模机理、建模过程,给出参数估计方法.并根据模型的基本形式,构建出以原始值和背景值的一阶累减生成序列的灰色相对关联度最大化为目标的灰色关联分析法来探索时滞参数Υ的确定方法,并获得模型的离散解.最后利用该模型对美国制造业库存总量进行了模拟预测,获得较高的精度,验证了模型的有效性.  相似文献   

11.
The grey prediction model, as a time-series analysis tool, has been used in various fields only with partly known distribution information. The grey polynomial model is a novel method to solve the problem that the original sequence is in accord with a more general trend rather than the special homogeneous or non-homogeneous trend, but how to select the polynomial order still needs further study. In this paper the tuned background coefficient is introduced into the grey polynomial model and then the algorithmic framework for polynomial order selection, background coefficient search and parameter estimation is proposed. The quantitative relations between the affine transformation of accumulating sequence and the parameter estimates are deduced. The modeling performance proves to be independent of the affine transformation. The numerical example and application are carried out to assess the modeling efficiency in comparison with other conventional models.  相似文献   

12.
逐步优化灰导数的非等间距GM(1,1)模型   总被引:1,自引:0,他引:1  
利用前向差商和后向差商的加权平均值代替灰导数,对非等间距灰色预测模型进行了改进,给出了加权系数的估计公式,并采用逐步递推的方法优化参数,建立新的非等间距GM(1,1)模型.最后通过实例证明了新模型具有较高的精度.  相似文献   

13.
基于灰导数和预测系数的GM(1,1)优化模型   总被引:1,自引:0,他引:1  
针对GM(1,1)模型的适用范围是近指数情况,提出了将优化灰导数与利用原始序列模拟的相对误差平方和最小估计预测系数c相结合的方法,从而得到一种简化计算的新GM(1,1)优化模型,该模型的预测公式x(0)(k)=ce-ak在形式上比较简洁,并且经严格指数序列从理论上验证了参数a具有白化指数律重合性,预测系数c具有白化系数重合性.  相似文献   

14.
A novel multivariate grey model suitable for the sequence of ternary interval numbers is presented in the paper. New model takes into account the influencing factors on the system behavior characteristic. New parameter setting makes the model directly applicable to the sequence of ternary interval number without the need to convert the sequence into real sequence. A compensation coefficient taken as a ternary interval number is added to the model equation. The accumulation method based on the new information priority is proposed to estimate coefficients. A connotative prediction formula is derived to replace the white response equation of the classical multivariate grey model. The single variable grey model, which takes into account the development trend of system behavior itself, is combined with the novel multivariate grey model based on the degree of grey incidence. Interval forecasts for China's electricity generation and consumer price index show that the new model has good performance.  相似文献   

15.
The multi-variable grey model based on dynamic background algorithm improves the forecasting performance of the multi-variable grey model on the precise number sequence. In order to make this model suitable for the interval sequence, the matrix form of the multi-variable grey model based on dynamic background algorithm is proposed in the paper. In the modeling process, the interval is treated as a two-dimensional column vector, the parameters of the multi-variable grey model are replaced by matrices, and the dynamic background algorithm for interval sequences is proposed. The analysis results of the matrix algorithm for the dynamic background value and the prediction formula show that the new model is essentially a way to predict one of the two bounds of an interval by combining them, reflecting the integrity and interaction between the lower and upper bounds. The interval predictions of industrial electricity consumption of Zhejiang Province, China national electricity consumption and consumer price index show that the new model can well predict the minimum and maximum values of the interval sequence and has better prediction performance compared with the method of predicting each boundary sequence separately.  相似文献   

16.
累加生成的改进和GM(1,1,t)灰色模型   总被引:5,自引:0,他引:5  
根据卷积变换可提高变换序列光滑度的特性和累加生成的机理,对灰色建模中的序列生成方式和GM(1,1)模型加以改进,用线性序列对建模序列作卷积变换,建立带线性时间项的灰色模型GM(1,1,t),实例计算结果表明GM(1,1,t)模型的模拟精度较GM(1,1)模型有较大提高且适用范围更广.  相似文献   

17.
In grey prediction modeling, the more samples selected the more errors. This paper puts forward new explanations of “incomplete information and small sample” of grey systems and expands the suitable range of grey system theory. Based on the geometric sequence, it probes into the influence on the relative errors by selecting the different sample sizes. The research results indicate that to the non-negative increasing monotonous exponential sequence, the more samples selected, the more average relative errors. To the non-negative decreasing monotonous exponential sequence, a proper sample number exists that has the least average relative error. When the initial value of the sequence of raw data of new information GM(1,1) model changes, the development coefficient remains unchanged. The segmental correction new information GM(1,1) model (SNGM) can obviously improve the simulation accuracy. It puts forward the mathematic proofs that the small sample usually has more accuracy than the large sample when establishing GM(1,1) model in theory.  相似文献   

18.
Accurate real-time prediction of urban traffic flows is one of the most important problems in traffic management and control optimization research. Short-term traffic flow has complex stochastic and nonlinear characteristics, and it shows a similar seasonality within intraday and weekly trends. Based on these properties, we propose an improved binding cycle truncation accumulated generating operation seasonal grey rolling forecasting model. In the new model, the traffic flow sequence of seasonal fluctuation is converted to a flat sequence using the cycle truncation accumulated generating operation. Then, grey modeling of the cycle truncation accumulated generating operation sequence weakens the stochastic disturbances and highlights the intrinsic grey exponential law after the sequence is accumulated. Finally, rolling forecasts of the limited data reflect the new information priority and timeliness of the grey prediction. Two numerical traffic flow examples from China and Canada, including four groups at different time intervals (1 h, 15 min, 10 min, and 5 min), are used to verify the performance of the new model under different traffic flow conditions. The prediction results show that the model has good adaptability and stability and can effectively predict the seasonal variations in traffic flow. In 15 or 10 min traffic flow forecasts, the proposed model shows better performance than the autoregressive moving average model, wavelet neural network model and seasonal discrete grey forecasting model.  相似文献   

19.
提出了一种结合非线性回归技术的灰色GM(1,1)模型的改进模型.利用我国的房地产价格指数预测作为研究对象,用以验证所提方法的有效性和准确性.根据实证结果,说明了新的改进模型有效提高了经典灰色模型的预测精度.  相似文献   

20.
在传统GM(1,1)模型基础上,结合最小二乘法原理提出:对本身已具有准指数规律的原始序列直接进行建模,并在此基础上对新模型背景值进行适当优化.克服传统GM(1,1)模型建模过程中的盲目性,并提高了拟合与预测精度.  相似文献   

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