Incumbency advantage and its value

Markets with network effects are typically concentrated. The aim of this paper is to discuss some recent work on “incumbency advantage.” That is, the fact that firms already installed generate higher profits than entrants even if the latter offer identical or even better terms (in terms of price and quality) to consumers. In particular, we review recently known sources of the advantage and potential mitigating factors and point to a number of open issues.     

Sample attrition in the RLMS, 2001–10

The data of the Russian Longitudinal Monitoring Survey (RLMS) – Higher School of Economics represents one of the few nationally representative sources of household and individual data for Russia. These data have been collected since 1992 and in recent years, thanks to more secure financial and logistical support, have become a resource increasingly drawn upon by scholars and students for national and cross-national studies. In this paper, we examine the extent of non-random attrition in the RLMS and discuss the circumstances under which this might give rise to biases in econometric analysis. We illustrate this with an example drawn from the health sphere.     

Application of graph theory to mining the similarity of travel trajectories

Travel mobility has attracted considerable attention from tourism scholars. Studies have extensively discussed discovering key (i.e., collective) movement patterns. Recently, the advancement of information technology has allowed tourism researchers to obtain detailed information regarding travel digital footprints. This study, which analyzes mobile sensor big data, proposes a data mining approach to measure the similarity of travel trajectories by performing a pair comparison of individual trajectory. This method considers the spatial and temporal dimensions of travel flow to help identify trajectory similarity across individual travelers. Considering graph theory, this research also applies graph-based spatiotemporal analytics to identify important insights from complex travel mobility networks. As a result, this study suggests an innovative approach to assess travel trajectory similarity, which can be regarded as a type of data-driven clustering method. This paper also demonstrates the applicability of network science in travel mobility.     

新粤浙管道工程管材采购质量控制措施与建议

针对新粤浙管道工程的特点,在对川气东送管道工程的管材采购经验进行总结的基础上,从管材标准制定、供应商管理、全过程质量控制及科学管理的角度,对采购质量控制问题进行了探讨,并提出了加强管材采购质量控制的措施和建议。     

The World Is Not Enough! Small Open Economies and Regional Dependence

In this paper, we explicitly introduce regional factors into a global dynamic factor model. We combine new open economy factor models (emphasizing global shocks) with the recent findings of regional importance in the business cycle synchronization literature. The analysis is applied to a large panel of domestic data for four small open economies. We find that global and regional shocks explain roughly 30 and 20 percent, respectively, of the business cycle variation in all countries. While global shocks have most impact on trade variables, regional shocks explain a relatively large share of the variation in cost variables.     

Do R&D and ICT affect total factor productivity growth differently?

We analyze the effect of ICT and R&D on total factor productivity (TFP) growth across different industries in Sweden. R&D alone is significantly associated with contemporaneous TFP growth, thus exhibiting indirect effects. Although there is no significant short-run association between ICT and TFP, we find a positive association with a lag of seven to eight years. Thus, R&D affect TFP much faster than ICT-investments. We also divide ICT capital into hardware and software capital. To our knowledge, this distinction has not been made in any previous study analyzing TFP at the industry level. The results show that lagged hardware capital services growth is significantly associated with TFP growth. Hence, investments complementary to hardware are needed to reap the long-run TFP effects from reorganizing production.     

An Empirical Investigation of Composite Product Choice

Prior ingredient branding research has examined the influence of “stated” factors such as fit between partner brands on composite product (e.g., Tide with Downy fabric softener) attitudes. This research focuses on choice of composite products, and addresses three managerially relevant questions: Which consumer segments are more likely to adopt the composite product? Will the choice of the composite product have positive or negative reciprocal effects on partner brands? Will the introduction of the composite product benefit the primary or the secondary brand more? The authors use a brand choice model to investigate the “revealed” choice of complements-based composite products. Study results indicate that (i) despite high fit between the composite product and the primary brand, consumer segments may have different choice likelihoods for these products, whereas prior research suggests equal likelihood; (ii) the choice of a composite product may not provide a positive reciprocal effect to the secondary brand; and (iii) the introduction of a composite product may benefit the primary brand more than the secondary brand, whereas prior research suggests a symmetrical benefit for the partner brands. Finally, the finding that introducing a composite product may not cannibalize the sale of the primary brand extends the ingredient branding literature, which has been silent on this issue.     

THE MEANING OF FAILED REPLICATIONS: A REVIEW AND PROPOSAL

The welcome rise of replication tests in economics has not been accompanied by a consensus standard for determining what constitutes a replication. A discrepant replication, in current usage of the term, can signal anything from an unremarkable disagreement over methods to scientific incompetence or misconduct. This paper proposes a standard for classifying one study as a replication of some other study. It is a standard that places the burden of proof on a study to demonstrate that it should have obtained identical results to the original, a conservative standard that is already used implicitly by many researchers. It contrasts this standard with decades of unsuccessful attempts to harmonize terminology, and argues that many prominent results described as replication tests should not be described as such. Adopting a conservative standard like this one can improve incentives for researchers, encouraging more and better replication tests.     

云计算相关问题及其在高校中的运用价值

云计算是计算机科学技术与网络互联技术结合创新发展的产物,已经成为引领未来世界信息产业的关键性技术和手段。云计算在教育领域体现出了很大优势,改进学习方式,改造学习环境,同时可以降低IT成本,对于提高高校现有资产的效率、利用率和灵活性具有重要影响意义。