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基于GWO-Prophet的商品销售预测研究
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作者 曾文烜 高永平 《计算机与数字工程》 2024年第3期659-664,699,共7页
零售企业的各项经营活动都离不开商品的销售情况,对商品的销售预测为企业制定生产计划与经营决策等活动提供重要的依据。针对企业销售额预测中销售额时间序列受外界条件影响大,预测精度低等问题,论文提出了一种基于GWO-Prophet的商品销... 零售企业的各项经营活动都离不开商品的销售情况,对商品的销售预测为企业制定生产计划与经营决策等活动提供重要的依据。针对企业销售额预测中销售额时间序列受外界条件影响大,预测精度低等问题,论文提出了一种基于GWO-Prophet的商品销售预测方法。基于某零售企业2015年-2018年销售额数据,通过Prophet模型将高维的销售额数据分别构建对应趋势项、季节项、节假日项、残差项的低维时序特征分量,分别用这些低维特征分量进行拟合后通过加法模型累加来预测未来一年的销售额数据;通过灰狼寻优算法(GWO)对Prophet模型参数进行智能寻优,防止模型陷入局部最优从而提高模型的精确度,通过灰狼寻优算法优化后的Prophet模型能更好地拟合突变点,季节项,节假日项等外界因素对销售额的影响。以MAE、MAPE和RMSE作为模型评估的指标,结果表明,基于GWO-Prophet模型的预测精度不仅优于单一的Prophet模型,还优于其他如ARIMA、SARIMA、LSTM对比模型。 展开更多
关键词 Prophet模型 GWO算法 时间序列 销售预测 可分解模型
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基于混合图模型的统计学课程关系分析 被引量:1
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作者 袁蕾 徐平峰 单娜 《长春工业大学学报》 CAS 2020年第3期219-223,共5页
分析某高校统计学专业学生31门课程的成绩,其中23门成绩为百分制,8门成绩为5级制。对5级制成绩忽略进行建模,利用混合图模型刻画课程之间的关系。
关键词 混合图模型 可分解模型 模型 森林模型 课程关系
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基于改进Prophet算法的短期日负荷预测方法研究 被引量:4
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作者 刘涅煊 杨学良 +2 位作者 陶晓峰 黄福兴 陆春艳 《电力需求侧管理》 2022年第5期58-63,共6页
将Prophet算法引入负荷预测领域,并结合XGBoost算法提升Prophet负荷预测准确性。Prophet算法基于时间序列分解及机器学习的拟合,将负荷数据分解为趋势项、周期项、随机波动项3部分,引入XGBoost算法改进Prophet算法对随机波动项的预测,将... 将Prophet算法引入负荷预测领域,并结合XGBoost算法提升Prophet负荷预测准确性。Prophet算法基于时间序列分解及机器学习的拟合,将负荷数据分解为趋势项、周期项、随机波动项3部分,引入XGBoost算法改进Prophet算法对随机波动项的预测,将XGBoost算法对随机波动的预测结果与Prophet算法对趋势项和周期项的预测结果叠加,获得最终的预测结果。该算法适用于用电负荷这种具备一定周期变化特征的序列,易于理解,预测准确性较高。通过某地区用电信息采集系统提供的专公变用户日冻结数据实验验证,结果表明在相同条件下,改进后的算法预测的结果的平均绝对误差百分比较原始的Prophet算法可降低2.5%,同时均方根误差降低幅度可达30.79%,体现出显著的改进效果。 展开更多
关键词 短期负荷预测 可分解模型 预测精度 PROPHET XGBoost
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Orthogonal nonnegative matrix factorization based local hidden Markov model for multimode process monitoring 被引量:3
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作者 Fan Wang Honglin Zhu +1 位作者 Shuai Tan Hongbo Shi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第7期856-860,共5页
Traditional data driven fault detection methods assume that the process operates in a single mode so that they cannot perform well in processes with multiple operating modes. To monitor multimode processes effectively... Traditional data driven fault detection methods assume that the process operates in a single mode so that they cannot perform well in processes with multiple operating modes. To monitor multimode processes effectively,this paper proposes a novel process monitoring scheme based on orthogonal nonnegative matrix factorization(ONMF) and hidden Markov model(HMM). The new clustering technique ONMF is employed to separate data from different process modes. The multiple HMMs for various operating modes lead to higher modeling accuracy.The proposed approach does not presume the distribution of data in each mode because the process uncertainty and dynamics can be well interpreted through the hidden Markov estimation. The HMM-based monitoring indication named negative log likelihood probability is utilized for fault detection. In order to assess the proposed monitoring strategy, a numerical example and the Tennessee Eastman process are used. The results demonstrate that this method provides efficient fault detection performance. 展开更多
关键词 Multimode processFault detectionHidden Markov modelOrthogonal nonnegative matrix factorization
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THE DATA ENVELOPMENT ANALYSIS MODEL WITH INTERSECTION FORM PRODUCTION POSSIBILITY SET 被引量:5
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作者 Quanling WEI Hong YAN 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2010年第6期1086-1101,共16页
The data envelopment analysis (DEA) model is used to evaluate the relative economic efficiency of a given set of decision making units (DMUs). In this paper, the DEA production possibility set is transferred from ... The data envelopment analysis (DEA) model is used to evaluate the relative economic efficiency of a given set of decision making units (DMUs). In this paper, the DEA production possibility set is transferred from the conventional sum form into the intersection form which is represented by a linear inequality system. Although it is time consuming to obtain the intersection form of the production possibility set, it suggests a new angle to investigate the properties of DMUs and to extend the DEA research further beyond the efficiency measurement. Following the intersection form, the analytical formula of the efficiency indicator and projection is given. Various aspects of technical efficiency, returns to scale and evidence of congestion of the DMUs are studied. The relationship between the weak DEA efficiency and the weak Pareto solution is discussed. Finally, a procedure for DMU grouping is proposed to help the decision makers for better resource reallocation and strategy adjustment. 展开更多
关键词 Data envelopment analysis intersection form production possibility set.
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IS TECHNICAL ANALYSIS INFORMATIVE IN UK STOCK MARKET? EVIDENCE FROM DECOMPOSITION-BASED VECTOR AUTOREGRESSIVE(DVAR) MODEL 被引量:2
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作者 XIE Haibin BIAN Jiangze +1 位作者 WANG Mingxi QIAO Han 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2014年第1期144-156,共13页
The paper proposes a new approach -- The decomposition-based vector autoregressive (DVAR) model to scrutinize the predictability of the UK stock market. Empirical studies performed on the monthly British FTSE100 ind... The paper proposes a new approach -- The decomposition-based vector autoregressive (DVAR) model to scrutinize the predictability of the UK stock market. Empirical studies performed on the monthly British FTSE100 index over 1984-2012 confirm that the DVAR model does provide informative forecasts for both in-sample and out-of-sample forecasts. Trading strategies based on the DVAR forecasts can Significantly beat the simple buy-and-hold, which demonstrates the valuable information provided by technical analysis in the UK stock market. 展开更多
关键词 DVAR stock market predictability technical analysis UK stock market.
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Indecomposable Calabi-Yau Objects in Stable Module Categories of Finite Type 被引量:1
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作者 Xiaolan YU Jiwei HE 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2011年第5期793-802,共10页
The authors give a discription of the finite representation type over an algebraically stable categories of selfinjective algebras of closed field, which admits indecomposable Calabi-Yau obdjects. For selfinjective al... The authors give a discription of the finite representation type over an algebraically stable categories of selfinjective algebras of closed field, which admits indecomposable Calabi-Yau obdjects. For selfinjective algebras with such properties, the ones whose stable categories are not Calabi-Yau are determined. For the remaining ones, i.e., those selfinjective algebras whose stable categories are actually Calabi-Yau, the difference between the Calabi-Yau dimensions of the indecomposable Calabi-Yau objects and the Calabi-Yau dimensions of the stable categories is described. 展开更多
关键词 Selfinjective algebra Stable category Calabi-Yau category Indecomposable Calabi-Yau object
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Bi-dimension decomposed hidden Markov models for multi-person activity recognition
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作者 Wei-dong ZHANG Feng CHEN Wen-li XU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第6期810-819,共10页
We present a novel model for recognizing long-term complex activities involving multiple persons. The proposed model, named ‘decomposed hidden Markov model’ (DHMM), combines spatial decomposition and hierarchical ab... We present a novel model for recognizing long-term complex activities involving multiple persons. The proposed model, named ‘decomposed hidden Markov model’ (DHMM), combines spatial decomposition and hierarchical abstraction to capture multi-modal, long-term dependent and multi-scale characteristics of activities. Decomposition in space and time offers conceptual advantages of compaction and clarity, and greatly reduces the size of state space as well as the number of parameters. DHMMs are efficient even when the number of persons is variable. We also introduce an efficient approximation algorithm for inference and parameter estimation. Experiments on multi-person activities and multi-modal individual activities demonstrate that DHMMs are more efficient and reliable than familiar models, such as coupled HMMs, hierarchical HMMs, and multi-observation HMMs. 展开更多
关键词 Multi-channel setting Hierarchical modeling Hidden Markov model Activity recognition
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On the Cellular Indecomposable Property of Semi-Fredholm Operators
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作者 Guozheng CHENG Xiang FANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2012年第6期903-908,共6页
The authors prove that an operator with the cellular indecomposable property has no singular points in the semi-Fredholm domain, by applying the 4 x 4 matrix model of semi-Fredholm operators due to Fang in 2004. This ... The authors prove that an operator with the cellular indecomposable property has no singular points in the semi-Fredholm domain, by applying the 4 x 4 matrix model of semi-Fredholm operators due to Fang in 2004. This result fills a gap in the result of Olin and Thomson in 1984. 展开更多
关键词 Cellular indecomposable property Semi-Fredholm operator Singular point
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