Stable Discovery of Interpretable Subgroups via Calibration in Causal Studies

Building on Yu and Kumbier's predictability, computability and stability (PCS) framework and for randomised experiments, we introduce a novel methodology for Stable Discovery of Interpretable Subgroups via Calibration (StaDISC), with large heterogeneous treatment effects. StaDISC was developed during our re-analysis of the 1999–2000 VIGOR study, an 8076-patient randomised controlled trial that compared the risk of adverse events from a then newly approved drug, rofecoxib (Vioxx), with that from an older drug naproxen. Vioxx was found to, on average and in comparison with naproxen, reduce the risk of gastrointestinal events but increase the risk of thrombotic cardiovascular events. Applying StaDISC, we fit 18 popular conditional average treatment effect (CATE) estimators for both outcomes and use calibration to demonstrate their poor global performance. However, they are locally well-calibrated and stable, enabling the identification of patient groups with larger than (estimated) average treatment effects. In fact, StaDISC discovers three clinically interpretable subgroups each for the gastrointestinal outcome (totalling 29.4% of the study size) and the thrombotic cardiovascular outcome (totalling 11.0%). Complementary analyses of the found subgroups using the 2001–2004 APPROVe study, a separate independently conducted randomised controlled trial with 2587 patients, provide further supporting evidence for the promise of StaDISC.     

Analysis of the relationship between the perceived extent of a tourist destination and smartphone use

Service Business - This study considers the relationship between lack of interest (as a leisure constraint), practical travel motivation (desire to visit famous and recommended destinations), and...     

From fantasy to reality: a study of pre-trip planning from the perspective of destination image attributes and temporal psychological distance

Pre-leisure trip planning is often lengthy, and its consideration shifts from fantasy to reality. Using overseas international cities as the destination, and through destination image attributes, this paper uses construal level theory and temporal psychological distance to understand the dynamics behind this shift. The shift is, by and large, as predicted by construal level theory. This study shows that tourists are consistently concerned about certain attributes as the shift unfolds. It is recognized that although tourism is dream packed, it is filled with risks and constraints. The shift also reflects tourists’ increasing needs to address practical issues and to fill their itinerary as a trip approaches. This study proposes that the destination information provision service offered by DMOs have to address the needs for tourists to ‘dream’ about a destination, allay their concerns, and help them schedule their itinerary at various phases of the pre-trip planning stage.     

The impact of sustained attention on labor market outcomes: The case of Ghana

In this paper, we go beyond traditional measures of cognitive abilities (IQ) in explaining labor market and social outcomes in developing countries. We exploit a rich dataset from Ghana that provides information on demographics, labor market outcomes, and a direct measure of cognitive ability along with other test scores to construct a measure of sustained attention. Our work is therefore related to the broader literature in psychology on the importance of executive function on individual behavior and outcomes. We find that, at least for the case of Ghana, after controlling for IQ and other covariates, higher levels of sustained attention are associated with higher educational attainment and a higher likelihood of being employed in a white‐collar job.     

Who likes jargon? The joint effect of jargon type and industry knowledge on investors’ judgments

We experimentally investigate how jargon affects investment willingness for investors with different industry knowledge, and whether such effects vary with good or bad jargon. We find that for investors without industry knowledge, jargon decreases investment willingness because it decreases understanding. However, for investors with some but low industry knowledge, jargon increases investment willingness because it increases perceived product premium. Such effects exist whether good or bad jargon is used. Finally, investors with high industry knowledge differentiate between good and bad jargon, and reduce investment willingness only when bad jargon is used. These findings have implications for regulators, managers, and investors.     

Firms’ heterogeneity,demand accumulating,and exchange rate pass-through

In this article, we study how the export behaviors of new and incumbent exporters differentially respond to exchange rate shocks. We establish a dynamic model, in which new exporters strategically charge a lower price than incumbent exporters to grow their customer base and increase future sales. The model predicts that new exporters adjust their prices more aggressively relative to their incumbent counterparts in response to exchange rate fluctuations. Using a transaction-level data set containing all Chinese exporters during the 2000–2009 period, we find supporting evidence for the model's predictions: new exporters adjust their price 1.5 times more than incumbent exporters. This, in turn, results in export quantities being less responsive to exchange rate shocks among new exporters. The result holds for a series of robustness checks. The findings imply that there are different degrees of exchange rate pass-through among new and incumbent exporters.     

Do major customers promote firms’ innovation?

This study examines whether and how a concentrated supply chain relationship affects a firm’s innovation decisions. Using data from Chinese listed firms in the manufacturing industry, we find that a concentrated customer base constrains a firm’s R&D investment, where a 1% increase in customer concentration is associated with a 0.011% decrease in R&D investment. To establish causality, we use the instrumental variable method, the reverse causality model, and the Granger causality test to re-examine the relationship and arrive at a consistent conclusion. Results from mechanism analysis suggest that a concentrated customer base constrains the internal fund availability and that the negative relationship between customer concentration and firms’ innovation is less pronounced for firms with more external financial support. Additional analysis reveals that the negative effect of customer concentration mainly affects R&D investment expenditure and that customer concentration also constrains innovation output in China. Overall, our paper reveals the dark side of close customer-supplier relationships and provides new insights into how supply chain relationships affect firms’ innovation decisions.     

5G毫米波焦点频段(26 GHz)全球研究动态与展望

阐述了5G系统毫米波焦点频段(26 GHz频段)全球频谱划分与现有应用概况，对全球研究动态与主要国家和地区的初步观点进行了梳理与总结。结合本频段现有无线电业务应用情况，重点剖析了开展频谱兼容性研究的关键场景、研究方法与主要挑战。最后，对5G系统有助于兼容共存的特征进行了归纳，为后续研究指明了方向。相关内容可为该频段5G频率规划提供借鉴。     

35kV配电设备安装调试的常见问题分析

35kV配电设备的安装调试工作是变电所施工中至关重要,其调试的成功与否直接关系到变电所的正常受电和安全运行,是变电所施工中的关键工序,须引起高度重视,而35kV变电所是国内变配电系统中十分重要的变配电装置,下面即是对常见问题的分析。     

对中国传统养生体育研究状况的再思考

中国传统养生体育历史悠久,是我国民族传统体育的一大宝贵遗产。在国内体育不断"西化"的今天,对其基础理论和发展趋势的研究由为重要。文章对中国传统养生体育的研究状况加以分析,讨论研究中出现的一些问题并提出相关的建议对策。