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1.
Environmental scanning is a broadly defined concept, having first received attention from scholars in the late 1960s. Over the years a number of similar and overlapping constructs have emerged in management literature. The aim of this study, via a systematic review and thematic analysis of relevant empirical research, is to consolidate foundation environmental scanning knowledge, demonstrate how scanning research has developed and fragmented over time, and propose an agenda for future research. The first contribution of our review is a new typology of environmental scanning research made up of five discrete research views, which provides a more comprehensive and contemporary overview of the field than previous studies. The second is a proposed agenda for future research that explicitly acknowledges the role of technology, an area that is presently underdeveloped in foundation scanning literature. The third contribution is to signpost future directions for research on scanning and organisational performance using a number of theoretical perspectives. The overall outcome of our review is to move scanning research on from increasingly incremental contributions concerned with context to a place where the changing role of technology and the mechanisms through which environmental scanning contributes to competitive advantage can be more thoroughly understood. 相似文献
2.
D. C. Wickramarachchi B. L. Robertson M. Reale C. J. Price J. A. Brown 《Australian & New Zealand Journal of Statistics》2019,61(3):380-391
We present an algorithm for learning oblique decision trees, called HHCART(G). Our decision tree combines learning concepts from two classification trees, HHCART and Geometric Decision Tree (GDT). HHCART(G) is a simplified HHCART algorithm that uses linear structure in the training examples, captured by a modified GDT angle bisector, to define splitting directions. At each node, we reflect the training examples with respect to the modified angle bisector to align this linear structure with the coordinate axes. Searching axis parallel splits in this reflected feature space provides an efficient and effective way of finding oblique splits in the original feature space. Our method is much simpler than HHCART because it only considers one reflected feature space for node splitting. HHCART considers multiple reflected feature spaces for node splitting making it more computationally intensive to build. Experimental results show that HHCART(G) is an effective classifier, producing compact trees with similar or better results than several other decision trees, including GDT and HHCART trees. 相似文献
3.
Public Organization Review - 相似文献
4.
Jiawen Chen Harvey J. Krahn Nancy L. Galambos Matthew D. Johnson 《Revue canadienne de sociologie》2019,56(1):30-48
Previous research on generativity, the desire to leave a legacy through establishing and guiding the next generation, has focused primarily on family life and civic engagement as pathways to midlife generativity. This paper proposes that intrinsically rewarding work can also be associated with a heightened sense of generativity in midlife. We test this hypothesis with data (n = 369 employed individuals, approximately 43 years old) from the 2010 wave of the Edmonton Transitions Study. Civic engagement was positively associated with midlife generativity, as predicted, but the hypothesized positive relationship between generativity and perceived parenting success was not found. Taking into account civic engagement and perceived parenting success, and controlling on a range of other variables, intrinsically rewarding work was positively associated with midlife feelings of generativity. 相似文献
5.
AbstractIn this essay, we offer our stories of family and migration under a Donald Trump presidency. We are a lesbian couple; one of us is a citizen of the United States while the other is a citizen of a Muslim country. We use autoethnographic methods to explore and interrogate our “messy and fabulous” journey of liminality; our journey of belonging and exclusion, where we grapple with issues related to sexuality, family, career, and citizenship. Our “voices” are used both individually and in unison, to highlight our intersectional and relational selves. We intend this work to contribute to the many ways we can better understand and appreciate the bountiful and colorful vistas of lesbian families’ migrant experiences. 相似文献
6.
Theory and Society - The massive expansion of US higher education after World War II is a sociological puzzle: a spectacular feat of state capacity-building in a highly federated polity. Prior... 相似文献
7.
Guanglei Yu Yang Li Liang Zhu Hui Zhao Jianguo Sun Leslie L. Robison 《Scandinavian Journal of Statistics》2019,46(2):414-431
This paper discusses regression analysis of panel count data with dependent observation and dropout processes. For the problem, a general mean model is presented that can allow both additive and multiplicative effects of covariates on the underlying point process. In addition, the proportional rates model and the accelerated failure time model are employed to describe possible covariate effects on the observation process and the dropout or follow‐up process, respectively. For estimation of regression parameters, some estimating equation‐based procedures are developed and the asymptotic properties of the proposed estimators are established. In addition, a resampling approach is proposed for estimating a covariance matrix of the proposed estimator and a model checking procedure is also provided. Results from an extensive simulation study indicate that the proposed methodology works well for practical situations, and it is applied to a motivating set of real data. 相似文献
8.
Proportional hazards are a common assumption when designing confirmatory clinical trials in oncology. This assumption not only affects the analysis part but also the sample size calculation. The presence of delayed effects causes a change in the hazard ratio while the trial is ongoing since at the beginning we do not observe any difference between treatment arms, and after some unknown time point, the differences between treatment arms will start to appear. Hence, the proportional hazards assumption no longer holds, and both sample size calculation and analysis methods to be used should be reconsidered. The weighted log‐rank test allows a weighting for early, middle, and late differences through the Fleming and Harrington class of weights and is proven to be more efficient when the proportional hazards assumption does not hold. The Fleming and Harrington class of weights, along with the estimated delay, can be incorporated into the sample size calculation in order to maintain the desired power once the treatment arm differences start to appear. In this article, we explore the impact of delayed effects in group sequential and adaptive group sequential designs and make an empirical evaluation in terms of power and type‐I error rate of the of the weighted log‐rank test in a simulated scenario with fixed values of the Fleming and Harrington class of weights. We also give some practical recommendations regarding which methodology should be used in the presence of delayed effects depending on certain characteristics of the trial. 相似文献
9.
Jamie M. Lawler Erika L. Bocknek Ellen W. McGinnis Cecilia Martinez‐Torteya Katherine L. Rosenblum Maria Muzik 《Infancy》2019,24(2):249-274
The current study examined the role of hypothalamic‐pituitary‐adrenal reactivity (a physiological indicator of stress) in early infancy as a mediator of the relationship between maternal postpartum depression and toddler behavior problems. Participants were 137 at‐risk mothers and their children participating in a longitudinal study of intergenerational transmission of risk. Mothers’ depression was measured five times during the infants’ first 18 months. Infant cortisol was collected during a social stressor (the still‐face paradigm) when infants were 6 months old, and mothers reported on toddlers’ internalizing and externalizing symptoms at 18 months. Among this sample of high‐risk mother–infant dyads, early postpartum depression predicted atypical infant cortisol reactivity at 6 months, which mediated the effect of maternal depression on increased toddler behavior problems. Clinical implications are discussed. 相似文献
10.
吕铖钢 《北京理工大学学报(社会科学版)》2021,23(2):152-160
税法中不确定概念下的理论空间以及税务行政的实践需求共同营造了税务行政裁量的制度空间,而不规范的税务行政裁量则为不规范的税收执法提供了操作机会。通过对税法文本中不确定概念理论缘由的寻求,以及税收征管中实践动因的梳理,税务行政裁量权的规范化确有必要性。为达成税法运行各司其职中的彼此制衡,有必要强化比例性原则在税务行政裁量中的运用,以此限制税权介入纳税人私域的范围与限度,并提供明确化的宏观指引;利用行政裁量基准“行政自制”与“规则之治”的双重品质,借助标准化的文本修正,为规范化的税收执法预设行为轨迹、构建外在制约并压缩裁量空间;以纳税人的同意权为基础,设计符合税法特殊性的程序规则,形成立体化的纳税人救济路径。最终形成税务行政裁量权积极运作与规范运行的制度环境。 相似文献