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901.
Prior competitive dynamics research has drawn on theories of information processing to model the subjective antecedents of executives' retaliation choices. This prior work has made great progress in developing our understanding of the retaliation choices most firms will make to a given type of attack. What the information processing perspective has not been able to do is explain firm‐specific behavior to predict which competitive moves individual firms will challenge, or explain why individual firms differ in the types of actions that they are most likely to challenge. The goal of this paper is to sharpen the theoretical and empirical focus on predicting firm‐level retaliation proclivities. We leverage managerial cognition research to examine the relationship between firm‐level differences in the cognitive frameworks that executives possess, and firm‐level differences in whether and how quickly firms challenge a market move. Results from a longitudinal study of the airline industry suggest that the addition of a cognitive perspective provides important insights into competitive retaliation. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
902.
环境绩效评价的引入和推广使建筑业越来越关注其自身活动对环境的影响。迄今,学术界对环境绩效评价的研究成果显著,不仅基于自然环境、社会环境、经济环境的三角关系形成可持续性评价的研究领域,还基于项目全生命周期管理创立了全生命周期评价的理论体系。基于文献综述和问卷调查,设计出一套适用于建设项目的环境绩效指标,并分析各指标的数据可获得性、重要性及应受关注度,为国内建设项目更加科学地进行环境绩效评价提供了理论支持。  相似文献   
903.
从文昌油田群油气水计量技术优化方案及实施效果的现场应用出发,阐述了多相流量计这一新型技术对油气田的产能配置、病态生产工况的诊断、油气井的维护和控制具有明显的技术优势和效果。  相似文献   
904.
全息成像提供了一种从单一观察点捕捉具有完整三维信息画面的可靠、快捷的方法。本文回顾了近期提出的单通道菲涅耳数字全息光学系统,该系统能获得由非相干光照射的三维实物体的全息图。在这一静态全息技术中,由三维物体反射或发射光,在通过空间光调制器(SLM)后,用数码相机记录。SLM被用作单通道非相干干涉仪的分束器,使来自物体上各点的球面波被分成两束具有不同曲率半径的球面波。所有球面波干涉结果的非相干总和,即可生成被观测物体的三维菲涅耳全息图。在计算机中可再现该全息图,使其三维特征得以呈现。  相似文献   
905.
基于内容分析的数据挖掘研究   总被引:1,自引:0,他引:1       下载免费PDF全文
原建伟 《河北工业科技》2011,28(5):299-301,342
采用计算机辅助内容分析软件Atlas.ti对开源社区用户学习行为进行定性分析,将分析后的结果导出为特定格式的XML文档,使用DOM对该文档解析后形成二维表形式数据,使之便于在数据库中存储,从而进行进一步的定量分析,为内容分析的后继研究提供了一种新的思路.  相似文献   
906.
In this paper, we use survey data to analyze the accuracy, unbiasedness and efficiency of professional macroeconomic forecasts. We analyze a large panel of individual forecasts that has not previously been analyzed in the literature. We provide evidence on the properties of forecasts for all G7-countries and for four different macroeconomic variables. Our results show a high degree of dispersion of forecast accuracy across forecasters. We also find that there are large differences in the performances of forecasters, not only across countries but also across different macroeconomic variables. In general, the forecasts tend to be biased in situations where the forecasters have to learn about large structural shocks or gradual changes in the trend of a variable. Furthermore, while a sizable fraction of forecasters seem to smooth their GDP forecasts significantly, this does not apply to forecasts made for other macroeconomic variables.  相似文献   
907.
This paper incorporates vintage differences and forecasts into the Markov switching models described by Hamilton (1994). The vintage differences and forecasts induce parameter breaks close to the end of the sample, too close for standard maximum likelihood techniques to produce precise parameter estimates. A supplementary procedure estimates the statistical properties of the end-of-sample observations that behave differently from the rest, allowing inferred probabilities to reflect the breaks. Empirical results using real-time data show that these techniques improve the ability of a Markov switching model based on GDP and GDI to recognize the start of the 2001 recession.  相似文献   
908.
This article provides a practical evaluation of some leading density forecast scoring rules in the context of forecast surveys. We analyse the density forecasts of UK inflation obtained from the Bank of England’s Survey of External Forecasters, considering both the survey average forecasts published in the Bank’s quarterly Inflation Report, and the individual survey responses recently made available to researchers by the Bank. The density forecasts are collected in histogram format, and the ranked probability score (RPS) is shown to have clear advantages over other scoring rules. Missing observations are a feature of forecast surveys, and we introduce an adjustment to the RPS, based on the Yates decomposition, to improve its comparative measurement of forecaster performance in the face of differential non-response. The new measure, denoted RPS*, is recommended to analysts of forecast surveys.  相似文献   
909.
Does aging influence structural change? Evidence from panel data   总被引:1,自引:0,他引:1  
Our study represents a first attempt to single out the effects of aging on the entire structure of the economy that is approximated by employment shares in different sectors. We find that even after controlling for the effects of other relevant factors - e.g., income per capita, share of trade in GDP, government consumption share in GDP, population size - aging does have a statistically significant differentiated impact on the employment shares. In particular, we find that an increase in aging exerts a statistically significant adverse effect on the employment shares in agriculture, manufacturing, construction, and mining and quarrying industries. At the same time, an increasing share of the elderly (decreasing share of the youth) in society positively affects employment shares in community, social, and personal services as well as in the financial sector.  相似文献   
910.
基于DEA的物流公司绩效评价   总被引:1,自引:0,他引:1  
王佟 《物流科技》2011,34(1):33-36
鉴于传统绩效评价方法的局限性,运用数据包络分析(DEA)法,并以2008和2009年19家中国物流上市公司为样本进行实证研究,为各物流企业客观了解和评价自身物流竞争力和相对物流绩效水平提供参考。  相似文献   
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