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1.
《International Journal of Forecasting》2022,38(4):1546-1554
The M5 competition uncertainty track aims for probabilistic forecasting of sales of thousands of Walmart retail goods. We show that the M5 competition data face strong overdispersion and sporadic demand, especially zero demand. We discuss modeling issues concerning adequate probabilistic forecasting of such count data processes. Unfortunately, the majority of popular prediction methods used in the M5 competition (e.g. lightgbm and xgboost GBMs) fail to address the data characteristics, due to the considered objective functions. Distributional forecasting provides a suitable modeling approach to overcome those problems. The GAMLSS framework allows for flexible probabilistic forecasting using low-dimensional distributions. We illustrate how the GAMLSS approach can be applied to M5 competition data by modeling the location and scale parameters of various distributions, e.g. the negative binomial distribution. Finally, we discuss software packages for distributional modeling and their drawbacks, like the R package gamlss with its package extensions, and (deep) distributional forecasting libraries such as TensorFlow Probability. 相似文献
2.
《International Journal of Forecasting》2022,38(4):1555-1561
Machine learning (ML) methods are gaining popularity in the forecasting field, as they have shown strong empirical performance in the recent M4 and M5 competitions, as well as in several Kaggle competitions. However, understanding why and how these methods work well for forecasting is still at a very early stage, partly due to their complexity. In this paper, I present a framework for regression-based ML that provides researchers with a common language and abstraction to aid in their study. To demonstrate the utility of the framework, I show how it can be used to map and compare ML methods used in the M5 Uncertainty competition. I then describe how the framework can be used together with ablation testing to systematically study their performance. Lastly, I use the framework to provide an overview of the solution space in regression-based ML forecasting, identifying areas for further research. 相似文献
3.
《International Journal of Forecasting》2022,38(4):1400-1404
This work presents key insights on the model development strategies used in our cross-learning-based retail demand forecast framework. The proposed framework outperforms state-of-the-art univariate models in the time series forecasting literature. It has achieved 17th position in the accuracy track of the M5 forecasting competition, which is among the top 1% of solutions. 相似文献
4.
5.
Showrooming, a phenomenon in which customers use brick-and-mortar stores to assess products and then purchase them from online retailers (o-retailers) for lower prices, is considered a great threat to traditional retailers (t-retailers). To combat showrooming, many t-retailers have executed price matching which enables customers to pay o-retailers' lower prices for the identical product. To avoid direct competition with t-retailers who execute price matching, many o-retailers have begun to sell differentiated products from t-retailers, which weakens the information advantage to customers from practicing showrooming. Motivated by these observations, we construct a duopoly game, where a t-retailer and an o-retailer sell products in a same category, to study the profitabilities of product differentiation and price matching in the context of showrooming. The results show that in the scenario without price matching, the o-retailer is likely to benefit from product differentiation only when the o-retailer's differentiated product is more popular with customers than the t-retailer's product. However, in the price matching scenario, the o-retailer also has the opportunity to benefit from product differentiation when the o-retailer's differentiated product is less popular with customers than the t-retailer's product, and product differentiation can be a win-win strategy for the two retailers under certain conditions. Considering the o-retailer's product differentiation decision, the t-retailer is only likely to execute price matching if the non-digital attributes of the product category sold by two retailers are not very obvious. 相似文献
6.
本文研究了银行竞争程度的变动对制造业上市公司融资约束大小的影响。本文将我国制造业A股上市公司作为样本,建立多元回归模型验证银行竞争形势的加剧是否会影响企业所面临的融资约束。本文认为制造业A股上市公司面临显著的融资约束,而且银行竞争与企业所面临的融资约束之间呈现U型关系,即随着银行竞争的加剧,融资约束呈现先放松后收紧的趋势。 相似文献
7.
《Socio》2021
Haze pollution has become a new threat to China's sustainable development, but it may be that local government behaviour can play an important role in the prevention and control of pollutants. A dynamic spatial autoregressive (SAR) model is used to study the relationship between local government competition and haze pollution. To further explore the indirect impact of factor market distortion on haze pollution and control potential endogeneity problems, a newly developed intermediary effect model that incorporates the characteristics of the generalized method of moments (GMM) is utilized to explore how factor market distortion indirectly affects haze pollution. The research results show that regional haze pollution in China is characterized by significant spatial correlation, and local government competition has a positive impact on haze pollution; that is, local government competition exacerbates haze pollution. In general, local government competition not only directly leads to an increase in haze pollution but also further intensifies it by distorting the local factor market, and the intermediary role of factor market distortion is approximately 7.04%. The results of the regional inspection found that competition among local governments in the eastern region did not lead to haze pollution, and distortion of the factor market did not exist as an intermediary effect. However, both direct and intermediary effects are significant in the central and western regions. Therefore, an official performance appraisal system that includes ecological constraints should be established to guide the benign transformation of local government competition, and an environmental management mechanism must be developed for joint prevention and control to reduce haze pollution. In addition, the free flow of factors and marketization are equally important. 相似文献
8.
This paper examines the existence and characteristics of pure-strategy Nash equilibria in oligopoly models in which firms simultaneously set prices and quantities. Existence of a pure-strategy equilibrium is proved for a class of price–quantity games. If the demand function is continuous, then the equilibrium outcome is similar to that of a price-only model. With discontinuous demand and limited spillover, there are rationing equilibria in which combined production falls short of market demand. Moreover, there might again be an equilibrium reflecting the outcome of a price game. Competition in price and quantity thus yields Bertrand outcomes under a variety of market conditions. 相似文献
9.
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
10.
By integrating the two areas of competition–performance and environment–performance, this research explores if competition matters in the relationship between environmental practices and interest margins in the market. A panel of 458 banks from 74 countries for the period of 2006–2016 is used, and the sample is further divided into developed and developing countries. This paper uses the system Generalized Method of Moments estimator to tackle potential omitted variable bias, endogeneity, and simultaneity issues. Without competition, environmental practices only affect banks in developing countries; however, the results show a significant impact for the full sample, including developed countries, when the competition is taken into consideration, suggesting that competition might play a role in the relationship of environmental practices and interest margins. In the full sample, competition impacts the relationship negatively after a moderate level of competition is reached in the market. The environmental practices in developing countries are prone to competition in the market. In developed countries, the competition is found to be lightly positively moderating the impact of environmental practices on interest margins. Based on these findings, it is recommended that developing countries should have a low or moderate level of competition to encourage environmental practices. For developed countries, however, high competition should be preferred to encourage banks to consider environmental practices as one of their core business strategies. These findings are found robust to different statistical estimators. 相似文献