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911.
Over the last ten years the concept of ‘competence’ has emerged as a central concept for competitive strategy. Several rich theoretical streams have contributed an extensive array of frameworks, definitions and papers using the concept. There is now a need to integrate these many contributions. Indeed, some of the frustration expressed recently by academics may be due to the large volume of conversation and the low level of integration. A concept that is considered so useful that many writers have incorporated it in their work will be of little value if it takes on different meanings for every use. If competence is to be used to explain relationships among variables and to build richer understandings of the roots of competitive advantage, then the field needs to engage in a serious conversation that attempts to focus this concept. Competence needs to be understood in a way that is faithful to its theoretical roots, allows the multiple dimensions that underpin competitive advantage to be meaningfully integrated and is specific enough that meaningful differences can emerge when used as a variable in empirical research. This paper seeks to begin a conversation toward that end by presenting a conceptualization that meets all of these requirements. The paper builds its conceptualization around satisfying the elements of a dynamic model of the relationship between competence and competitive advantage. 相似文献
912.
913.
Over two dozen operationalizations of board composition can be identified from the empirical literature. A structural equations confirmatory factor analysis (LISREL 8.03) suggests that these operationalizations do not constitute a single construct of board independence. Instead, analyses strongly indicate three separate constructs. Common operationalizations of board composition, then, are neither tenable surrogates for one another nor are they interchangeable. Implications for empirical aggregation of studies, theory/measurement convergence, and the current corporate governance public policy debate are discussed. 相似文献
914.
In an investigation of 418 employees in the Norwegian Postal Service, employees with high learning opportunities and high decision authority were found to be better off on psychological functioning, health and organizational outcome variables than employees with low scores on these variables. Decision authority and learning opportunities had specific and independent impact on subjective health, psychological functioning, coping style and organizational outcome variables. There were, however, also interaction effects between demands, learning opportunities, and decision authority on subjective health. Learning opportunities and decision authority were operationalized with a questionnaire, supplemented with questions on the opportunities to learn skills beyond the present job situation. It is suggested that this is a particularly important dimension for coping with the present day rapid changes in working life, where the objective for many workers will be to broaden their repertoire and competence to increase their flexibility in the labour market. 相似文献
915.
本文建立了火焰原子吸收光谱法测定硫酸中铁和锌的方法。确定了最佳仪器工作条件和样品处理方法。在选择好的实验条件下,测定铁的特征浓度为0.014μg/mL/1%吸收;测定锌的特征浓度为0.002μg/mL/1%吸收。回收率分别为铁98.8%—103.4%,锌92.5%—98.6%。 相似文献
916.
The objective of this study was to determine the impact of task information (TI) provided by an interface agent during the idea evaluation and integration step of the problem formulation stage of the problem solving process. The effectiveness assessment was based on solving diagnostic decision problems in the domain of complex industrial machinery. Ten domain experts participated in this study. Decision support was provided by a case-based reasoning system. Findings suggest that TI provided by the interface agent had no effect on the decision maker's performance, nor on the associated cognitive effort. However, a verbal protocol analysis revealed that the ten subjects used the interface agent to verify their decision processes. The results and their implications are discussed with respect to current findings in the area of decision support systems. 相似文献
917.
This paper proposes and empirically validates a stages of growth model for the evolution of Information Systems Planning (ISP). A questionnaire survey of senior IS executives is used to gather information pertaining to the stages of growth model, which includes measurement of the nature and level of integration between business planning (BP) and ISP. The del test is used to validate empirically benchmark variables for each stage of BP-ISP integration. The results support the stages of growth model of BP-ISP integration and the benchmark variables are generally found to be successful in predicting the stage of integration. 相似文献
918.
Michael R. Crager 《Journal of applied statistics》2012,39(2):399-417
The standardized hazard ratio for univariate proportional hazards regression is generalized as a scalar to multivariate proportional hazards regression. Estimators of the standardized log hazard ratio are developed, with corrections for bias and for regression to the mean in high-dimensional analyses. Tests of point and interval null hypotheses and confidence intervals are constructed. Cohort sampling study designs, commonly used in prospective–retrospective clinical genomic studies, are accommodated. 相似文献
919.
P. Berchialla S. Snidero A. Stancu C. Scarinzi R. Corradetti 《Journal of applied statistics》2012,39(4):867-874
Bayesian networks (BNs) are probabilistic expert systems which have emerged over the last few decades as a powerful data mining technique. Also, BNs have become especially popular in biomedical applications where they have been used for diagnosing diseases and studying complex cellular networks, among many other applications. In this study, we built a BN in a fully automated way in order to analyse data regarding injuries due to the inhalation, ingestion and aspiration of foreign bodies (FBs) in children. Then, a sensitivity analysis was carried out to characterize the uncertainty associated with the model. While other studies focused on characteristics such as shape, consistency and dimensions of the FBs which caused injuries, we propose an integrated environment which makes the relationships among the factors underlying the problem clear. The advantage of this approach is that it gives a picture of the influence of critical factors on the injury severity and allows for the comparison of the effect of different FB characteristics (volume, FB type, shape and consistency) and children's features (age and gender) on the risk of experiencing a hospitalization. The rates it consents to calculate provide a more rational basis for promoting care-givers’ education of the most influential risk factors regarding the adverse outcomes. 相似文献
920.
D. R. Cox Man Yu Wong 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2004,66(2):395-400
Summary. Given a large number of test statistics, a small proportion of which represent departures from the relevant null hypothesis, a simple rule is given for choosing those statistics that are indicative of departure. It is based on fitting by moments a mixture model to the set of test statistics and then deriving an estimated likelihood ratio. Simulation suggests that the procedure has good properties when the departure from an overall null hypothesis is not too small. 相似文献