Complements and substitutes in online product recommendations: The differential effects on consumers’ willingness to pay

Online product recommendations have been shown to influence consumers’ preferences and purchasing behaviors for recommended products. However, it remains an open empirical question whether and how recommendations of other products affect a consumer’s economic behavior for a focal product. In many e-commerce websites, a product is presented with co-purchase and co-view recommendations, which potentially contain complementary and substitutable products, respectively. Very little research has explored differential effects of recommending complementary and substitutable products. In this study, we explore how types of other recommended products impact consumers’ willingness to pay for a focal product through interactions with prices of recommended products and consumers’ decision stages. We conducted a 2³ randomized factorial experiment as well as two 2 × 2 experiments to examine these issues. Experimental results provide evidence that there is a significant interaction effect between the recommendation type and decision stage, which highlights the importance of recommendation timing on e-commerce platforms. Furthermore, it also illustrates that the effect of recommending complementary vs. substitutable products is subject to contextual factors such as consumers’ decision stages. Results of our study have significant implications for the design and application of online recommender systems.     

1—1—二氟乙烷气体比热的实验测量和理论计算

1-1-二氟乙烷(R152a)对大气臭氧层没有破坏作用,是制冷剂R12(二氟二氯甲烷)的有希望的替代物之一。本文在流动式高压气体比热实验台上测量了R152a气体的定压比热。温度范围为313～353 K,压力范围为0.4～2.3 MPa。为检验实验装置的可靠性和准确度,测定了R22气体的定压比热,经与文献值比较,测量偏差小于0.4％。本文还应用统计热力学中的微扰理论对所测范围内的测量点进行了比热的理论计算,计算结果与本文实验值的平均相对偏差为1.42％。     

聚氨酯硬泡氯氟烃发泡剂替代技术的新进展

对聚氨酯硬泡工业CFC发泡剂的4种替代路线和最新进展作了简单综述。     

Polynomial time algorithm for an optimal stable assignment with multiple partners

This paper considers the many-to-many version of the stable marriage problem where each man and woman has a strict preference ordering on the members of the opposite sex that he or she considers acceptable. Further, each man and woman wishes to be matched to as many acceptable partners as possible, up to his or her specified quota. In this setup, a polynomial time algorithm for finding a stable matching that minimizes the sum of partner ranks across all men and women is provided. It is argued that this sum can be used as an optimality criterion for minimizing total dissatisfaction if the preferences over partner-combinations satisfy a no-complementarities condition. The results in this paper extend those already known for the one-to-one version of the problem.     

邻苯--EO酸酯及其环保增塑剂的代用品开发

该文以主要篇幅推荐一批已经开发并工业化生产和正在研究开发的增塑剂品种，包括对苯二甲酸酯、苯多酸多酯、二元酸酯、聚酯、植物油基和环氧植物油和柠檬酸酯等系列产品。性能良好，环境友好。     

几种CFCs代用工质的PVTx实验研究

在对实验方法进行探讨的基础上,对HFC32、RFC143a、HCFC142b和二元混合物系HCFC22/HFC152a等CFCs替代工质进行了PVTx实验研究。蒸汽压和过热区PVTx实验精度为|△T|<28mK、|△P|<1.4kPa、|△v/v|<0.1％、|△x|<0.01％;采用直接观察泡点法测量纯质饱和液体密度精度为|△T|<38mK、|△ρ/ρ|<0.05％。基于界面消失位置和临界乳光现象测定了HFC32的临界密度为ρ_c=430±4Kg/m~3、临界温度T_c=351.28±0.05K,结合本文所给蒸汽压方程得出临界压力为P_c=5.801±0.008MPa。     

发泡剂的研究现状与发展趋势

概述了发泡剂的发展、分类及国内外生产与应用情况。     

The role of biodiversity products as incentives for conserving biological diversity: some instructive examples

Most of the world’s biodiversity is found in countries of the ‘South,’ yet much of the demand for biodiversity conservation comes from the citizens of countries in the ‘North’. Biodiversity is an important source of medicinal properties that are highly valued in the North and of traits that may improve and stabilize agricultural productivity worldwide. Does this mean that a market for rights to medicinal and agricultural traits from biodiversity could constitute a major incentive for biodiversity conservation in the South? Here we draw upon several case studies that suggest the answer is in general negative. Those who want to conserve existing levels of biodiversity should not assume that they can free ride on the conservation incentives provided via the market for pharmaceuticals and agricultural products.     

信息化要素与能源要素之间的关系研究

关于信息化要素与能源要素关系的研究还相对较少。本文选取了27个行业1986～2012年的数据对两者之间的关系进行了验证。检验结果显示,我们国家从80年代中期至今,信息化资本要素与能源要素之间呈现互补关系。有6个行业,分别是普通机械制造业、电气电子机械制造业、运输设备制造业、交通运输仓储及邮电通讯业、电力、批发和零售贸易及餐饮业,在这些行业中信息化要素与能源要素之间呈现替代关系;其余行业中,信息化要素与能源要素之间呈现互补关系。     

氟氯碳化合物及其替代产品的开发

在1996年前将停止氟氯碳化合物的生产和使用。本文概述了“氟氯碳问题”,以及氟氯碳化合物替代品和替代技术的开发现状,并针对我国情况提出了建议。