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181.
Laura Czerniewicz Sarah Goodier Robert Morrell 《Information, Communication & Society》2017,20(3):386-405
The networked age promises global digital cultures with flattened power relations, given the affordances of information and communication technologies to collapse distance, enable easier cross-country collaborations and create new opportunities for knowledge production and sharing. In the academic domains, indications are that knowledge patterns continue to reflect physically based geopolitical realities – where knowledge from the South is still peripheral while knowledge from the North still dominates in terms of all the conventional metrics. This study explores the potential role of digital affordances to challenge structural Northern bias and generates questions about knowledge production and dissemination in the climate change knowledge domain. It is framed by the field of scholarly communication within an African setting and by the emergent field of climate change which is fraught with debates and contestations, particularly regarding mitigation and adaptation. It draws on Southern theory which interrogates the global dynamics of knowledge production and dissemination. It explores the intersection of the discoverability and visibility of local climate change research methodologically from the outside in, through an experiment of searches for ‘climate change/South Africa’ and from the inside out by reviewing the online presence of one climate change group in a top-ranked African university. 相似文献
182.
Robert Q Pollard Jr. Brian T. Berlinski 《Journal of social work in disability & rehabilitation》2017,16(3-4):261-275
ABSTRACTForensic evaluation of deaf individuals presents unique challenges due to many examinees’ fund of information deficits, potential for language deprivation, and examiners’ frequent lack of creativity regarding communication methods. This article describes challenges most frequently encountered in competency to stand trial and criminal responsibility evaluations and offers strategies for overcoming them. The value of employing multiple communication methods, especially the use of illustrations, is emphasized. Suggestions also are offered regarding preparing evaluation reports and effectively communicating “key deaf fundamentals” to legal personnel. Encouragement is offered for qualified, sign-fluent professionals to engage in forensic work. 相似文献
183.
Yang Lei Susan Carlson Lisa N. Yelland Maria Makrides Robert Gibson 《Journal of applied statistics》2017,44(8):1466-1478
This research was motivated by our goal to design an efficient clinical trial to compare two doses of docosahexaenoic acid supplementation for reducing the rate of earliest preterm births (ePTB) and/or preterm births (PTB). Dichotomizing continuous gestational age (GA) data using a classic binomial distribution will result in a loss of information and reduced power. A distributional approach is an improved strategy to retain statistical power from the continuous distribution. However, appropriate distributions that fit the data properly, particularly in the tails, must be chosen, especially when the data are skewed. A recent study proposed a skew-normal method. We propose a three-component normal mixture model and introduce separate treatment effects at different components of GA. We evaluate operating characteristics of mixture model, beta-binomial model, and skew-normal model through simulation. We also apply these three methods to data from two completed clinical trials from the USA and Australia. Finite mixture models are shown to have favorable properties in PTB analysis but minimal benefit for ePTB analysis. Normal models on log-transformed data have the largest bias. Therefore we recommend finite mixture model for PTB study. Either finite mixture model or beta-binomial model is acceptable for ePTB study. 相似文献
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185.
In this article, we investigate the potential usefulness of the three-parameter transmuted generalized exponential distribution for analyzing lifetime data. We compare it with various generalizations of the two-parameter exponential distribution using maximum likelihood estimation. Some mathematical properties of the new extended model including expressions for the quantile and moments are investigated. We propose a location-scale regression model, based on the log-transmuted generalized exponential distribution. Two applications with real data are given to illustrate the proposed family of lifetime distributions. 相似文献
186.
Robert M. Mnatsakanov 《统计学通讯:理论与方法》2017,46(7):3174-3185
Two approximations recovering the functions from their transformed moments are proposed. The upper bounds for the uniform rate of convergence are derived. In addition, the comparisons of the estimates of the cumulative distribution function and its density function with the empirical distribution and the kernel density estimates are conducted via a simulation study. The plots of recovered functions are presented for several examples as well. 相似文献
187.
In this paper, the focus is on sequential analysis of multivariate financial time series with heavy tails. The mean vector and the covariance matrix of multivariate non linear models are simultaneously monitored by modifying conventional control charts to identify structural changes in the data. The considered target process is a constant conditional correlation model (cf. Bollerslev, 1990), an extended constant conditional correlation model (cf. He and Teräsvirta, 2004), a dynamic conditional correlation model (cf. Engle, 2002), or a generalized dynamic conditional correlation model (cf. Capiello et al., 2006). For statistical surveillance we use control charts based on residuals. Further, the procedures are constructed for t-distribution. The detection speed of these charts is compared via Monte Carlo simulation. In the empirical study, the procedure with the best performance is applied to log-returns of the stock market indices FTSE and CAC. 相似文献
188.
189.
Robert J. Cramer Amanda C. La Guardia Claire Bryson Kelley Morgan 《Journal of American college health : J of ACH》2017,65(6):363-371
Objective: To analyze the overlap of nonsuicidal self-injury (NSSI) and suicide-related behaviors (SRB) among college students with regard to demographics, mental health, and coping styles. Participants: Respondents were 572 undergraduate students at a southwestern public university. Methods: Data were collected in 2015. Respondents completed a demographic survey and assessments of NSSI, SRB, internalizing symptoms (ie, anxiety, stress, and depression), aggression, and negative coping strategies. The survey was administered via a Web-based procedure. Results: Women reported more frequent cutting behaviors than men. Endorsement of NSSI was also associated with an increased likelihood of lifetime SRB. A subgroup of students endorsing both NSSI and SRB demonstrated poorer mental health, more negative coping, and self-reported female sex. Conclusions: College healthcare providers may benefit from competency-based training in techniques for the combination treatment of NSSI and SRB, as well as culturally based models of suicide. 相似文献
190.
W. Parker Frisbie Ph.D. Douglas Forbes Robert A. Hummer Starling G. Pullum 《Demography》1998,35(4):519-527
In a recent article (Frisbie. Forbes. and Pullum 1996) we documented racial/ethnic differences in birth outcomes according to a more fine-grained classification than has typically been employed in the demographic literature. In his commentary, van der Veen focuses on the measurement of one of the dimensions of that classification, maturity of the infant. as proxied by the fetal growth ratio. The crux of the critique is easily seen in van der Veen's statement that “all of my disagreements with Frisbie et al. 's method arise from their particular use of a postnatal standard for the assessment of intrauterine growth.” Our critic misunderstands our objective: He fails to realize our interest in birth outcome, not pregnancy process, and does not perceive that our intent was to extend the research extant in both the demographic and public-health literatures in which patently postnatal (i.e., ex utero) measures are taken as outcomes interesting in their own right and/or as risk factors for infant mortality and infant and childhood morbidity. Specifically, he does recognize that we purposefully expanded our focus to include moderately compromised births to determine if they were at higher risk than the normal births with whom they are conventionally categorized. Our discussion draws on research cited in the original article, on studies cited by our critic, and on a few more recent investigations. Although we have never argued that ours is the only, or even the best, approach in all cases, we try to clarify the rationale for, and adduce additional empirical evidence of, the utility of the method we used. 相似文献