Competitive advantage: A longitudinal analysis of the roles of data-driven innovation capabilities,marketing agility,and market turbulence

While data-driven innovation capabilities have received considerable attention from academics and practitioners, there is insufficient longitudinal evidence on how they might contribute to improved marketing agility and competitive advantage. In this study, we make a preliminary effort to address this gap by developing a model based on the dynamic capabilities view. We also explore the moderating effects of market turbulence on the link among marketing agility and competitive advantage. We used two-waves data (T = 677 and T+1 = 569) and the cross-lagged panel approach was utilised to analyse the longitudinal data. Our findings provide robust empirical evidence on the causal and predictive temporal impact of data driven innovation capabilities on marketing agility and competitive advantage. It also indicated that marketing agility mediates this relationship over time. Moreover, the analysis suggested that market turbulence reinforce the influence of marketing agility on competitive advantage. We provided significant implications for theory and practice.     

突发事件下决定供应链敏捷力的关键要素研究北大核心

突发事件引起供应链中断或失效而造成商品断供或滞销的情况,对供应链敏捷力提出了新的要求。本文在全面梳理供应链敏捷力理论内涵的基础上,对新冠肺炎疫情期间283家复工复产企业进行调查,实证分析了决定供应链敏捷力的关键要素及其对供应链敏捷力的直接作用以及各要素之间的二阶交互调节作用。研究发现:市场响应对供应链敏捷力的正向促进作用不明显,但有显著的正向调节作用;物流服务则对供应链敏捷力正向促进作用明显,而正向调节作用几乎不存在;协调一致、供应能力、制造能力对供应链敏捷力均起正向作用,其中协调一致最为显著。在突发事件下,协调一致在某种形式上表现为“集中管理”模式,它有助于提高供需匹配的时效性。     

变频器在给水系统中的应用

针对高层建筑给水系统的特点，提出了变频调速在一定条件下具有节能、调节特性好、控制灵活及运行可靠等特点，给出了用一台变频器控制多台水泵的一种节能控制方案     

Daily news sentiment and monthly surveys: A mixed-frequency dynamic factor model for nowcasting consumer confidence

Policymakers, firms, and investors closely monitor traditional survey-based consumer confidence indicators and treat them as an important piece of economic information. To obtain a daily nowcast of monthly consumer confidence, we introduce a latent factor model for the vector of monthly survey-based consumer confidence and daily sentiment embedded in economic media news articles. The proposed mixed-frequency dynamic factor model uses a Toeplitz correlation matrix to account for the serial correlation in the high-frequency sentiment measurement errors. We find significant accuracy gains in nowcasting survey-based Belgian consumer confidence with economic media news sentiment.     

How does investor attention matter for crude oil prices and returns? Evidence from time-frequency quantile causality analysis

This paper studies the time–frequency, nonlinear quantile relationship between investor attention (GSVI) and crude oil over the period from January 2000 to April 2020. To do so, the wavelet coherency, wavelet-based causality-in-quantiles test and quantile-on-quantile method are employed. The results indicate that first, the correlation between investor attention and crude oil is relatively high, and the highly correlated regions are concentrated from 8 to 16 months. In most cases, the GSVI is negatively correlated with the crude oil market. Additionally, under extreme market conditions, the explanatory ability is stronger than in the normal market, and it is greater in the low-frequency domain than in the high-frequency domain. Finally, investor attention has an apparent asymmetric impact on crude oil prices and returns at each scale, displaying a positive effect on the low quantiles of crude oil but a negative effect on the high quantiles across all quantiles of the GSVI. In the short term, when crude oil prices and returns are in a bear market, the larger volume of the GSVI has a greater impact on them. Moreover, the impact becomes greatest under extreme market conditions.     

全球5G频谱研究概述及启迪

第五代移动通信系统（5G）已成为全球信息通信技术的重点发展方向，受到政府和行业的广泛关注。首先，对国际电信联盟无线电通信部门（ITU-R）建议书中发布的5G愿景进行了概述和分析，指出5G系统将使用高中低全频段；然后，总结了全球主要国家和地区关于5G频率政策的最新动向，分析了其高中低频段候选频率的当前使用情况和未来可用性，并指出了我国对相关频段的策略和考虑；最后，基于我国无线电管理政策及面临的形势，结合5G系统特性，提出了对于5G频率研究工作的思考和建议。     

正交空时分组码在OFDM系统中的性能估计

在宽带OFDM系统中对正交空时分组码方案进行了研究，根据Almouti方案的译码原理给出了在正交空时分组码传输的频率选择性衰落信道条件下接收机输出瞬时信噪比的一般表达式，同时分两种情况进一步分析了其最小距离球界的符号差错性能。结果表明，在系统发送天线数、接收天线数及多径数目乘积较小的情形下，系统可以达到最大的分集增益。     

Uniting partners to cope with environmental uncertainty: Disentangling the role of social capital in developing supply chain agility

Based on social capital theory, in this study, we investigate how a firm utilized social capital to coordinate partners in the achievement of supply chain agility under different levels of environmental uncertainty. We test the proposed hypotheses via a hierarchical regression analysis using questionnaire survey data collected from 190 firms in China. The empirical results show that cognitive, relational, and structural capital positively influence supply chain agility. Furthermore, environmental uncertainty positively moderates the positive relationship between relational capital and supply chain agility, whereas environmental uncertainty negatively moderates the positive roles of cognitive and structural capital. The findings suggest managers should adopt different strategies when leveraging social capital according to the business environment. In unpredictable and volatile business environments, managers should motivate their firms to embrace relational capital to obtain sufficient resources for achieving supply chain agility.     

New evidence of extreme risk transmission between financial stress and international crude oil markets

We aim to analyze the risk transmission between financial stress and crude oil under different shocks, with applying a novel Granger causality test. Recent works suggest that this risk transmission is mixed, however, scholars mainly focus on their average causality but neglect the extreme causality and its time-varying characteristic. Using the weekly data of the financial stress index and WTI prices spanning from 1994 to 2020, we employ the extreme time-domain and frequency-domain Granger causality test to conduct our research. Results obtained from the time-domain test imply that their causality generally originates from extreme shocks rather than non-extreme shocks, which hasn’t been found before. For further distinguishing the long-run and short-run effects of these shocks, we apply the frequency-domain test and discover that these causalities are mainly found for long the run. Thus, investors and policy-makers may benefit from monitoring financial stress, especially under long-term extreme conditions.     

Local CEOs,career concerns and voluntary disclosure

I study whether the management guidance provided by local chief executive officers (CEOs) differs from the guidance provided by nonlocal CEOs. The geographic preferences of the CEOs lead to segmented executive labor markets, which impose higher relocation costs and give rise to lower job mobility. I find that local CEOs, who grew up in the same states where the firm headquarters are located, provide fewer items in guidance and less frequent guidance than nonlocal CEOs. I also show that local CEOs have greater asymmetric withholding of bad news relative to good news and that they increase their disclosure during economic downturns in their home states. Collectively, these findings suggest that the geographically segmented CEO labor markets play an important role in the disclosure choices of CEOs.