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1.
对1978-2011年重庆市生产总值时间序列进行分析,研究发现四阶差分之后,数据趋于平稳;四阶差分序列的自相关系数一阶截尾,最终建立时间序列ARIMA(1,4,1)模型,并测算残差平方和,但ARIMA模型的残差序列存在自相关,对拟合效果产生了影响;基于时间序列ARIMA(1,4,1)模型研究的基础,进一步采用线性神经网络对序列进行学习和仿真计算,结果表明:神经网络的模拟效果优于ARIMA时间序列的模拟效果.  相似文献   

2.
杨君哲  吴静  王娟  刘潋  李强 《科技信息》2012,(32):139-140
本文运用时间序列模型(ARIMA模型)对中国人口进行分析与预测,应用Eviews6.0软件对1949~2007年中国人口数据进行拟合,建立ARIMA模型,运用2008~2010年的人口数据来验证模型,并对2011年的总人口数进行了预测。  相似文献   

3.
为了提高预测模型的精度,给出了一种新的组合预测模型.利用时间序列ARIMA预测模型、BP神经网络及GM灰色预测模型进行单一模型的拟合与预测,通过赋予适当权系数结合三种方法得到了新的组合预测模型.山西省人均GDP预测实例应用结果表明:组合预测模型很好地描述了山西省人均GDP的非线性发展,比单一预测方法具有更高的预测精度.组合模型发挥了这三种模型各自的优势,可以作为人均GDP预测的有效方法,该模型在时间序列的预测中是有效的.  相似文献   

4.
把趋势外推模型和ARIMA模型结合起来可构建混合时间序列这一新的预测模型.利用该模型,并以1978~2000年我国GDP总量数据为依据,通过Eviews5.0软件对模型进行估计,并根据建立的新模型对2001~2004年GDP总量作预测效果检验.结果表明,通过混合时间序列模型实施预测,误差相对较小,效果更好.  相似文献   

5.
根据19782012年安徽省城乡居民收入的时间序列数据,运用ARIMA模型,用SAS软件进行拟合,对安徽省城乡居民收入差距情况进行分析,给出了20132012年安徽省城乡居民收入的时间序列数据,运用ARIMA模型,用SAS软件进行拟合,对安徽省城乡居民收入差距情况进行分析,给出了20132015年安徽省城乡居民绝对收入差距的预测值。结果显示城乡居民收入差距会继续扩大。  相似文献   

6.
利用1961—2016年山东省济南市太阳年总辐射量观测数据,通过模型识别和统计检验,对比分析时间序列模型AR(5)和ARIMA((1,2,4),1,0)的拟合结果。残差检验结果表明,疏系数模型ARIMA ((1,2,4),1,0)可用于预测地表太阳年总辐射量,预测结果显示2017—2025年济南市地表太阳辐射的年际变化整体呈增长趋势。对比多元线性回归模型结果,时间序列疏系数模型误差较小,预测准确度相对较高。  相似文献   

7.
在分析ARIMA(p,d,q)预测模型的基础上,以福州市1961-2006年的雷暴日为时间序列基础,通过对该序列进行平稳性分析、差分处理、自相关、偏自相关系数计算与绘图、ARIMA建模、参数估计、假设检验及模型预测,将ARIMA模型运用在雷暴日的趋势分析上.研究结果表明,ARIMA能很好地拟合计算出未来短时段内的数据,...  相似文献   

8.
湖北省1999-2008年生态足迹动态测度与分析   总被引:1,自引:0,他引:1  
燕子  苏欣欣  李红伟 《河南科学》2011,29(5):623-625
运用生态足迹的理论和模型,对湖北省1999-2008年的生态足迹、生态承载力和万元GDP生态足迹进行了时间序列测度.计算结果表明:在这10年里,湖北省人均生态足迹、人均生态承载力以及GDP持有量一直在增加,但人均生态足迹的增长趋势远大于人均生态承载力;万元GDP生态足迹则一直呈现下降趋势.总体来说,湖北省1999-20...  相似文献   

9.
通过选取1978~2017年湖南省国内生产总值的相关数据,运用计量经济软件Eviews8对选取的时间序列数据进行模型的建立。再经过相对误差分析和所建Holter-Winter非季节短期预测模型的对比,最终确定建立ARIMA(1,1,2)最优模型来对湖南省GDP进行预测。研究发现,湖南省将在2020年达到全面建成小康社会并人均生产总值将超过一万美元,由此为今后湖南省决策机构制订宏观调控目标与进行经济决策时提供参考。  相似文献   

10.
本文利用时间序列分析线性模型中求和自回归移动平均模型(ARIMA)和统计学软件SPSS,选用1947-2014年新生儿人口数据为参考数据序列,通过参数检验与残差分析验证ARIMA模型在人口预测分析上的可靠性.模型的拟合与实证分析说明时间序列分析在人口预测问题上的有效性,可对中国婴儿潮做短期预测.本文还对2015年到2030年新生儿人口数进行统计分析,预测第四次婴儿潮的到来.这将给社会计划生育、教育、交通等方面提供重要参考数据.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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