Performance effects of innovation in two-sided markets: The paradigmatic case of OTAs

Online Travel Agents (OTAs) play an important intermediary role in the two-sided travel distribution market. A critical factor that enhances a firm's competitive advantage is innovation. Yet, the analysis of innovation in the OTA context is scarce. The main objective of this article is to fill this gap and examine the effect of OTA innovations on firm performance. We analyze the effect of two-sided market specific innovations (same-side and cross-side) on performance and contribute to the literature by expanding the theoretical understanding of innovations. We find that producer-to-consumer innovations have a greater effect on OTA performance than producer-to-producer and consumer-to-consumer innovations. A fundamental managerial implication is that exchange management is an area to be enhanced when innovating in travel market distribution.     

我国“一带一路”沿线地区风险投资时空分布及影响因素研究

深入分析我国“一带一路”沿线地区风险投资时空格局及影响因素，有助于促进创新创业与企业发展、提高区域科技创新水平。运用空间分析方法和空间计量模型，对2003-2018年我国“一带一路”沿线139个城市风险投资的时空分布特征及影响因素进行分析，结果表明：①沿线地区的风险投资发展具有不均衡性，呈现为沿海高、西部低的分异格局；②风险投资的全局自相关系数均为正，呈现出明显的空间集聚特征；③风险投资机构数、国家高新区数量、风险投资退出、政府引导基金发展、财政科技支出对区域风险投资具有显著促进作用，环境污染对风险投资有一定抑制作用。随着ESG投资理念逐渐获得认可，沿线地区可以通过提升绿色发展水平促进风险投资发展。     

M5 competition uncertainty: Overdispersion,distributional forecasting,GAMLSS, and beyond

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.     

Planning the delivery of relief supplies upon the occurrence of a natural disaster while considering the assembly process of the relief kits

Models for the distribution of relief supplies often assume immediate availability of relief items upon the occurrence of a natural disaster. However, such an assumption does not always apply in realistic settings. In some cases, at least it is necessary to assemble relief items into kits before distributing them among the affected population. This paper presents a rolling horizon methodology that considers dynamic parameters such as demand, capacities and demand priorities for the problem of distributing relief supplies after the occurrence of a natural disaster by including such assembling activities before the delivery.     

国防产业联盟协同创新网络政府治理：基于语义挖掘技术的策略向度研究

国防产业联盟发展的关键在于科学管理协同创新网络。政策注意力聚焦点反映政府治理创新网络的策略向度，不同政府层级间的注意力分布结构差异表明该策略向度的偏向性。通过人工构建主题词袋，计算主题词TF-IDF权值及余弦相似度，对中央和地方共96份政策文件、1 926份新闻文章进行规模化语义分析，整体评估政府治理国防产业联盟协同创新网络的策略适应性，并测量其在实施与宣传过程中的偏向性。结果发现，网络拓展是首要策略选择，网络管理方式为引导而非参与，关系耦合度低，网络愿景策略运用有限。地方政府在实施过程中出现了策略偏异和策略调整；政策宣传更接近地方政府的策略向度。     

Logistics optimization through a social approach for food distribution

The management of supply chains is becoming more important in economic and social environments. Currently, the social sustainability is a factor that must be considered to design governmental strategies and policies. The objective of this research paper was to show, with a case study an approach to optimize distribution and delivery logistics of food in a social assistance program of school breakfast using mathematical models that include transportation distance, optimal locations, and vehicle routing through different clusters. By using qualitative variables like poverty levels, food insecurity and social exclusion, different clustering methods are proposed with the purpose of identifying the common characteristics in the studied population; and at the same time, reducing the distribution complexity. The results show an efficient approach to design a supply chain that includes economic and social factors. The new model developed in this paper can be used to plan social assistance governmental programs, to identify the specific needs and characteristics of the beneficiaries, minimizing the total cost of the distribution network logistics when delivering food for school meals.     

Specialization dynamics

This paper proposes a new empirical framework for analyzing specialization dynamics. A country’s pattern of specialization is viewed as a distribution across sectors, and statistical techniques for analyzing the evolution of this entire distribution are employed. The empirical framework is implemented using data on 20 industries in seven OECD countries since 1970. We find substantial mobility in patterns of specialization. Over time horizons of 5 years, this is largely explained by forces common across countries, including world prices and common changes in technical efficiency. Over longer time horizons, country-specific changes in factor endowments become more important. There is no evidence of an increase in countries’ overall degree of specialization.     

Why parallel trade may raise producers' profits

This paper shows that a manufacturer may benefit from parallel trade. In addition to an intuitive condition about the effect of demand shocks, this occurs when competitive retailers must order inventories before they know the realization of demand and for products whose sale value drops at the end of the demand period. For these types of products, letting retailers trade unsold inventories generally results in larger orders placed with the manufacturer and higher manufacturer profit. The model provides a simple explanation as to why the volume of parallel trade is now very large and accepted by manufacturers for some products such as automobiles, clothes, toys, consumer electronics, musical recordings, cosmetics and perfumes.     

中美双边工业品增加值贸易隐含碳福利核算与分配问题研究

现代贸易方式不仅导致贸易利益在全球价值链上进行分配,还带来了贸易隐含污染排放在全球贸易网络中的分布。两国之间的贸易利益分配除了表现为贸易经济福利的分配,还表现为贸易隐含碳福利的分配。本文将贸易增加值分解法结合MRIO模型对2000—2014年中美双边工业品贸易增加值所隐含的碳福利分配及影响机制展开深入分析。研究结果表明:(1)在中美双边工业品增加值贸易隐含碳福利分配中,碳福利逆差在中国,碳福利顺差在美国;(2)中美工业品贸易碳福利级差经历了“先扩大,后收窄”的过程,美国次贷危机之后双边碳福利不平衡状况重新呈现扩大趋势;(3)中国碳排放强度下降、价值链地位提升以及对美进口规模扩大都有助于改善碳福利逆差的局面,但美国对中国不断扩大的中间品和最终品需求以及双边复杂的技术关联结构仍是中国碳福利逆差的主导因素;(4)全球价值链的深化可能将导致对出口国加征关税会通过降低进口消费侧排放的方式恶化加征国的贸易隐含碳福利。本文研究的时间范围同时覆盖中国加入WTO以及美国次贷危机两个重要节点,这对于重新审视中美经贸关系新格局下双边贸易隐含碳福利分配构建了一个新的分析视角,为中美未来贸易谈判以及全球碳排放责任认定提供了一个新的解读方向。     

Closed-form Bayesian inferences for the logit model via polynomial expansions

Articles in Marketing and choice literatures have demonstrated the need for incorporating person-level heterogeneity into behavioral models (e.g., logit models for multiple binary outcomes as studied here). However, the logit likelihood extended with a population distribution of heterogeneity doesn’t yield closed-form inferences, and therefore numerical integration techniques are relied upon (e.g., MCMC methods). We present here an alternative, closed-form Bayesian inferences for the logit model, which we obtain by approximating the logit likelihood via a polynomial expansion, and then positing a distribution of heterogeneity from a flexible family that is now conjugate and integrable. For problems where the response coefficients are independent, choosing the Gamma distribution leads to rapidly convergent closed-form expansions; if there are correlations among the coefficients one can still obtain rapidly convergent closed-form expansions by positing a distribution of heterogeneity from a Multivariate Gamma distribution. The solution then comes from the moment generating function of the Multivariate Gamma distribution or in general from the multivariate heterogeneity distribution assumed. Closed-form Bayesian inferences, derivatives (useful for elasticity calculations), population distribution parameter estimates (useful for summarization) and starting values (useful for complicated algorithms) are hence directly available. Two simulation studies demonstrate the efficacy of our approach. JEL Classification C6 · C8 · M3