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1.
《International Journal of Forecasting》2022,38(4):1319-1324
This note updates the 2019 review article “Retail forecasting: Research and practice” in the context of the COVID-19 pandemic and the substantial new research on machine-learning algorithms, when applied to retail. It offers new conclusions and challenges for both research and practice in retail demand forecasting. 相似文献
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ABSTRACT The purpose of this research is to analyze whether the Brazilian economy behaved under a wage-led or profit-led regime between 1960 and 2011, considering a Post-Kaleckian model in a context of external constraints. The time span is limited by data availability (i.e., 2011). To answer the question of whether the Brazilian economy works under a wage-led or profit-led regime, we propose a simple Post-Kaleckian model. The model suggests that a profit-led regime is more probable for Brazil. Moreover, a wage-led regime occurs when a balance of payments constrained growth model is taken into consideration. Likewise, the real exchange rate has a positive impact on economic growth through the export channel. This result is a novelty in the recent literature about the relationship between real exchange rate and economic growth within a Post-Kaleckian model. The Brazilian economy was chosen as it is one of the biggest economies in Latin America. 相似文献
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Predicting consumption behavior is very important for adjusting supplier production plans and enterprise marketing activities. Conventional statistical methods are unable to accurately predict green consumption behavior because it is characterized by multivariate nonlinear interactions. The paper proposes an optimized fruit fly algorithm (FOA) and extreme learning machine (ELM) model for consumption behavior prediction. First, to address the problem of uneven search direction of FOA leading to insufficient search ability and low efficiency, the paper proposes a sector search mechanism instead of a random search mechanism to improve the global search ability and convergence speed of FOA. Second, to address the issue that the initial weights and hidden layer bias values of the ELM are randomly generated, which affects the learning efficiency and generalization of the ELM, the paper uses an improved FOA to optimize the weights and bias values of ELM for improving the prediction accuracy. Taking the green vegetable consumption behavior of Beijing residents as an example, the results show the optimization of the initial weight and threshold of ELM by the GA, PSO, FOA, and SFOA, the prediction accuracy of the GA-ELM, PSO-ELM, FOA-ELM, and SFOA-ELM models all surpass those of ELM. Compared with BPNN, GRNN, ELM, GA-ELM, PSO-ELM, and FOA-ELM models, the RMSE value of SFOA-ELM was decreased by 9.45%, 8.40%, 11.89%, 5.84%, 2.22%, and 2.69%, respectively. These findings demonstrate the effectiveness of the SFOA-ELM model in green consumption behavior prediction and provide new ideas for the accurate prediction of consumption behaviors of other green products with similar characteristics. 相似文献
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The quest for authenticity in dining experiences has become increasingly important. This paper explores authenticity dimensions that are of value to customers in dining experiences, and by that gains a multi-dimensional understanding of authenticity in this context. Following an integrated learning approach using text mining and classification techniques, this paper explores and confirms different dimensions of authenticity by identifying and classifying authenticity judgements in online restaurant reviews. The results suggest that authenticity is a multi-dimensional concept encompassing Authenticity of the Other, Authenticity of the Producer, and Authenticity of the Self as first-level dimensions. Additionally, besides historical and categorical authenticity which have been previously explored in the literature, a new type of authenticity - Deviated Authenticity - emerged as a second-level dimension falling under Authenticity of the Other. This paper enhances existing conceptualisations of authenticity and establishes avenues for exploring the multi-dimensionality of other consumer research concepts using user-generated content. 相似文献
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立足众创时代特征,运用文献计量对1999—2018年间1701篇国内外众创文献挖掘分析,探寻众创经济特点主题,探析众创发展知识基础,探求众创研究演进脉络,并获取众创经济视域下核心语句和高频词语,运用扎根理论对抽取的126篇的众创文献样本进行三级编码,进而构建众创研究的整合性理论框架,探究众创研究的系统性发展图景。研究表明,众创理论假说大量问世,众创文献热点主题包括六类,众创经济研究存在两种演进趋势,众创经济治理系统理论具有三个维度;未来应关注众创主体思辨性、众创要素系统性和众创技术本土化等专题研究。 相似文献
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Byungjun Yu Saixing Zeng Hongquan Chen Xiaohua Meng Chiming Tam 《Business Strategy and the Environment》2021,30(1):1-20
Family firms bear two types of agency costs, including type I and type II agency problems, in corporate environmental practices: (1) Outside executives at family firms hesitate to engage in environmental strategies, which can lead to drops in profits; (2) Controlling families employ opportunistically environmental management to achieve their interests. We argue that a primary cause for the agency problems lies on ineffective internal corporate governance at family firms, which can cause loss of managerial (or power) balance between outside executives and family executives. Our findings show that family firms with ownership and strategic control (FSC), which family executives and outside executives monitor and constrain each other, can achieve the highest environmental performance. Moreover, external controls, including product market competition and provincial environmental regulations, substitute effective internal control of FSC. The environmental performance premium of FSC is more prevalent when the production market competition is lower. Family firms with ownership, operational, and strategic control (FOSC) can achieve higher environmental performance within a province with more stringent environmental regulations. 相似文献
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深度学习方法在作物遥感分类中的应用和挑战 总被引:1,自引:0,他引:1
[目的]准确估算作物的面积和分布对粮食安全至关重要。与传统的机器学习方法相比,深度学习具有多种优势,如端到端训练、可迁移性。为有效利用高时空数据进行作物识别提供了新的机遇。已有多种模型被应用于作物分类任务中,针对不同的分类任务,如何有效地选择模型,并对其进行训练和使用已成为关键问题。[方法]文章回顾了利用深度学习模型对作物分类的主要研究。N维卷积神经网络(N-D CNN)(N=1、2、3)和递归神经网络(RNN)已被有效用于作物分类任务。长短期记忆RNN(LSTM RNN)和门控循环单元RNN(GRU RNN)是RNN的变体,解决了随着时间序列增加RNN出现的梯度消失或爆炸问题。此外,还有研究使用CNN和RNN(我们称为RCNN)的混合模型对作物进行分类。该文首先阐述了使用深度学习方法进行作物制图的背景和意义,并介绍了CNN和RNN模型结构。然后回顾了一些典型的研究,包括模型的结构、遥感数据源、数据处理方法和分类精度。最后,总结了使用深度学习方法进行作物分类的挑战以及现有解决方案的局限性。[结果](1)1-D CNN可用于提取时间特征,或时间+光谱特征,分类效果良好;2-D CNN已被广泛应用于单时相数据的空间特征提取,分类精度依赖于数据源;3-D CNN应用较少,但具有很大的潜力,尤其是时间+空间维度的特征提取;(2)相同条件下(架构、数据源、研究区域、类别),LSTM RNN和GRU RNN分类效果通常高于普通RNN,而前两者的效果差距不大,但GRU RNN训练时间较短;(3)CNN+RNN混合模型(RCNN)用RNN比3-D CNN更适合提取时间特征。这主要是由于RNN建立了对序列数据的长期依赖,而3-D CNN卷积核是局部计算的。[结论]通过分析,认为深度学习技术是作物遥感分类的有效工具。此外,与其他模型相比,RCNN,3-D CNN和GUR RNN具有更大的潜力。 相似文献
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Drawn on the upper echelons theory, this study investigates how chief executive officer (CEO) hometown identity drives firm green innovation. We propose that CEO hometown identity has a positive impact on a firm's green innovation performance. Furthermore, we explore the moderating role of managerial discretion determined by organizational and environmental factors (i.e., institutional ownership and market complexity). We propose that institutional ownership negatively moderates the positive relationship between CEO hometown identity and green innovation, but market complexity plays a positive moderating role. Using Chinese publicly listed firms from 2002 to 2016 in heavily polluting industries, our findings support these hypotheses. Our research contributes to the upper echelons theory and corporate social responsibility literature and has substantial practical implications. 相似文献