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1.
Desirable system performance in the face of threats has been characterized by various management concepts. Through semistructured interviews with editors of journals in the fields of emergency response and systems management, a literature review, and professional judgment, we identified nine related and often interchangeably used system performance concepts: adaptability, agility, reliability, resilience, resistance, robustness, safety, security, and sustainability. A better understanding of these concepts will allow system planners to pursue management strategies best suited to their unique system dynamics and specific objectives of good performance. We analyze expert responses and review the linguistic definitions and mathematical framing of these concepts to understand their applications. We find a lack of consensus on their usage between interview subjects, but by using the mathematical framing to enrich the linguistic definitions, we formulate comparative visualizations and propose distinct definitions for the nine concepts. We present a conceptual framing to relate the concepts for management purposes.  相似文献   
2.
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.
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   
4.
Estimates of population characteristics such as domain means are often expected to follow monotonicity assumptions. Recently, a method to adaptively pool neighbouring domains was proposed, which ensures that the resulting domain mean estimates follow monotone constraints. The method leads to asymptotically valid estimation and inference, and can lead to substantial improvements in efficiency, in comparison with unconstrained domain estimators. However, assuming incorrect shape constraints may lead to biased estimators. Here, we develop the Cone Information Criterion for Survey Data as a diagnostic method to measure monotonicity departures on population domain means. We show that the criterion leads to a consistent methodology that makes an asymptotically correct decision choosing between unconstrained and constrained domain mean estimators. The Canadian Journal of Statistics 47: 315–331; 2019 © 2019 Statistical Society of Canada  相似文献   
5.
ABSTRACT

Grandfamilies, family structures in which grandparent(s) co-reside with and assume a primary caregiving role for at least one grandchild, are increasingly common in the United States. This qualitative, exploratory study, informed by family communication patterns theory (FCPT), illuminated the reported communication beliefs and practices of grandparents who serve as primary caregiver to at least one grandchild. Hybrid thematic analysis, combining FCTP with inductive analysis, was used to analyze 21 semi-structured interviews with grandparents. Results yielded four themes describing grandparents’ reported communicative practices: creating opportunities for listening and dialogue, talking about emotion, emphasizing openness, and allowing questioning; and three themes describing the impact of second-chance parenting: increased resources, acquired wisdom, and matured emotionally. Implications for grandfamily communication research in light of hybrid analyses and FCPT are discussed.  相似文献   
6.
ABSTRACT

The aim of this article was to identify and discuss ecosocial changes and community resilience mechanisms in a coastal fishing community of Sweden – Bönan. Data were collected through eight semi-structured interviews and field observations. An abductive thematic analysis was used to analyze data and background literature. The findings showed that Bönan has been exposed to a combination of ecosocial changes that have transformed the community, and therefore required community resilience interventions. This article concludes that social workers need to take an active part in ecosocial work for enhancing community resilience.  相似文献   
7.
8.
The aim of this article is to review existing goodness-of-fit tests for the exponential distribution under progressive Type-II censoring and to provide some new ideas and adjustments. In particular, we consider two-parameter exponentially distributed random variables and adapt the proposed test procedures to our scenario if necessary. Then, we compare their power by an extensive simulation study. Furthermore, we propose five new test procedures that provide reasonable alternatives to those already known.  相似文献   
9.
In social research, the use of agree/disagree (A/D) questions is a popular method for measuring attitudes. Research has shown that A/D questions require complex cognitive processing and are susceptible to response bias. Thus, some researchers recommend the use of item-specific (IS) questions. This study examines the processing of A/D and IS questions, using eye-tracking methodology. By recording respondents’ eye movements, how respondents process survey questions can be evaluated. The results reveal that IS questions cause more and longer fixations. However, this only applies to the response categories. There are no differences regarding the question stems. Altogether, it seems that IS response categories trigger deeper cognitive processing than A/D response categories.  相似文献   
10.
This paper explores liminality, a concept receiving increased attention in management and organization studies and gaining prominence because of its capacity to capture the interstitial and temporary elements of organizing and work. The authors present a systematic review of the literature on liminality, covering 61 published papers, and undertake a critical analysis of how the concept of liminality has been used in prior research. This review reveals associations with three main themes: process; position; and place. For each theme, the authors identify the central research questions posed, while comparing individual and collective levels of analysis. During this process, the authors revisit several ideas central to the original, anthropological research on liminality, a perspective from which they suggest a rejuvenation of liminality research in management and organization studies. This paper argues for a greater focus on the liminal experience itself – especially its ritual and temporal dimensions – and for improving the comparative analysis of liminality following the three themes identified in this paper. The authors suggest that revising the agenda for liminality research along these lines could facilitate more informed responses to the challenges of an increasingly temporary and dynamic work life.  相似文献   
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