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971.
J. Ravichandran 《统计学通讯:理论与方法》2019,48(16):3976-3991
In this article, Six Sigma zone control charts (SSZCCs) are proposed for world class organizations. The transition probabilities are obtained using the Markov chain approach. The Average Run Length (ARL) values are then presented. The ARL performance of the proposed SSZCCs and the standard Six Sigma control chart (SSCC) without zones or run rules is studied. The ARL performance of these charts is then compared with those of the other standard zone control charts (ZCCs), the modified ZCC and the traditional Shewhart control chart (SCC) with common run rules. As expected, it is shown that the proposed SSZCC outperforms the standard SSCC without zones or run rules for process shifts of any magnitude. When compared to the other standard ZCCs and the Shewhart chart with common run rules, it is observed that the proposed SSZCCs have much higher false alarm rates for smaller shifts and hence they prevent unwanted process disturbances. The application of the proposed SSZCC is illustrated using a real time example. 相似文献
972.
Nicholas Gelling Matthew R. Schofield Richard J. Barker 《Australian & New Zealand Journal of Statistics》2019,61(2):189-212
The rjmcmc package for R implements the post‐processing reversible jump Markov chain Monte Carlo (MCMC) algorithm of Barker & Link. MCMC output from each of the models is used to estimate posterior model probabilities and Bayes factors. Automatic differentiation is used to simplify implementation. The package is demonstrated on two examples. 相似文献
973.
974.
Postpartum Depression (PPD) affects approximately 9 - 20% of women. Many women with PPD go undiagnosed and/ or do not follow through on referrals for treatment. Although the most routinely prescribed treatments for PPD are antidepressant medication and psychotherapy, a significant number of women desire non-traditional options. This article provides a systematic review of ten recently published, randomized clinical trials in the examination of the effectiveness of complementary health approaches—the use of non-mainstream products and interventions—on PPD. A search of nine databases of the English language literature from the years 2006 to 2018 was performed. Review criteria included published work, utilization of randomized-controlled trials, and the use of a reliable and valid measurement tool to identify cases of PPD and monitor changes in symptom severity. The studies reviewed focused on the following interventions: aromatherapy, bright light therapy, electroacupuncture, infant massage, iron supplementation, mindfulness training, omega-3 fatty acids, saffron, and yoga. Outcomes demonstrate the feasibility and safety of these approaches, as well as varying degrees of effectiveness. While many were pilot studies using small sample sizes, the results are encouraging and substantiate the need for additional trials. Studies are summarized and limitations and implications for social work and future research are described. 相似文献
975.
Adrian J. Archuleta 《Social Work in Mental Health》2019,17(3):302-322
Negative evaluative beliefs and other cognitive structures have been tied to psychological distress across various populations but have not been sufficiently incorporated into acculturation models. The current study examines the relationships between acculturation and various activating events and mediating sources of support related to negative evaluative beliefs among people of Mexican descent (N = 319). Overall, model variables explained 26% of the variance in negative evaluative beliefs. Acculturation, marital commitment, and social capital associated with friends were negatively related to negative evaluative beliefs. Conversely, single relationship status, marital reward value, psychosocial stressors, and bridging social capital were positively related, and likely serve as activating events for negative evaluative beliefs. Identifying mechanisms related to psychological distress as well as supportive structures may help in constructing interventions that will address the specific needs of different groups. Future research should continue to explore appraisal and associated beliefs in acculturation models to understand why acculturative experiences may become stressful. 相似文献
976.
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
977.
Stephen J. Ruberg Frank E. Harrell Jr. Margaret Gamalo-Siebers Lisa LaVange J. Jack Lee Karen Price 《The American statistician》2019,73(1):319-327
ABSTRACTThe cost and time of pharmaceutical drug development continue to grow at rates that many say are unsustainable. These trends have enormous impact on what treatments get to patients, when they get them and how they are used. The statistical framework for supporting decisions in regulated clinical development of new medicines has followed a traditional path of frequentist methodology. Trials using hypothesis tests of “no treatment effect” are done routinely, and the p-value < 0.05 is often the determinant of what constitutes a “successful” trial. Many drugs fail in clinical development, adding to the cost of new medicines, and some evidence points blame at the deficiencies of the frequentist paradigm. An unknown number effective medicines may have been abandoned because trials were declared “unsuccessful” due to a p-value exceeding 0.05. Recently, the Bayesian paradigm has shown utility in the clinical drug development process for its probability-based inference. We argue for a Bayesian approach that employs data from other trials as a “prior” for Phase 3 trials so that synthesized evidence across trials can be utilized to compute probability statements that are valuable for understanding the magnitude of treatment effect. Such a Bayesian paradigm provides a promising framework for improving statistical inference and regulatory decision making. 相似文献
978.
979.
Probabilistic integration of a continuous dynamical system is a way of systematically introducing discretisation error, at scales no larger than errors introduced by standard numerical discretisation, in order to enable thorough exploration of possible responses of the system to inputs. It is thus a potentially useful approach in a number of applications such as forward uncertainty quantification, inverse problems, and data assimilation. We extend the convergence analysis of probabilistic integrators for deterministic ordinary differential equations, as proposed by Conrad et al. (Stat Comput 27(4):1065–1082, 2017. https://doi.org/10.1007/s11222-016-9671-0), to establish mean-square convergence in the uniform norm on discrete- or continuous-time solutions under relaxed regularity assumptions on the driving vector fields and their induced flows. Specifically, we show that randomised high-order integrators for globally Lipschitz flows and randomised Euler integrators for dissipative vector fields with polynomially bounded local Lipschitz constants all have the same mean-square convergence rate as their deterministic counterparts, provided that the variance of the integration noise is not of higher order than the corresponding deterministic integrator. These and similar results are proven for probabilistic integrators where the random perturbations may be state-dependent, non-Gaussian, or non-centred random variables.
相似文献980.
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