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11.
M. Rae Moors 《Information, Communication & Society》2019,22(6):808-822
ABSTRACTThe Flint Water Crisis became a national news story in January of 2016, when major publishers such as The New York Times began covering the story. In the same month, an influx of social media activism occurred in response to the crisis, with citizens developing hashtag campaigns such as #FlintFwd in order to disseminate news and stories from a citizen’s perspective; these campaigns often positioned Flint positively ? as a recovering community ? rather than a city in the middle of a public health crisis, and often addressed not a national public but a local audience. This paper considers Flint-based social media activity to investigate the emergence of place-based activism within the ostensibly global network of social media. In doing so, it identifies three key themes; 1) leveraging social media to forward a critique of deficient journalistic storytelling; 2) using the affective process of storytelling via social media to claim authority over their own material offline existence, and 3) using place-based storytelling to implicate others as witnesses via the global network of social media. These themes coalesce around a distinctly critical logic of connectivity. This logic extends the notion of connectivity articulated by Van Dijck and Poell [2013. Understanding social media logic. Media and Communication, 1(1), 2–14.] and the strategies of platform activism explored by Tufekci [2017. Twitter and tear gas: The power and fragility of networked protest. New Haven: Yale University Press.] to explain how social media works to expose discrepancies between the public story of the water crisis and material, lived conditions of Flint, rendering visible a discursive identity of Flint thus far unrecognized. 相似文献
12.
Researchers have been developing various extensions and modified forms of the Weibull distribution to enhance its capability for modeling and fitting different data sets. In this note, we investigate the potential usefulness of the new modification to the standard Weibull distribution called odd Weibull distribution in income economic inequality studies. Some mathematical and statistical properties of this model are proposed. We obtain explicit expressions for the first incomplete moment, quantile function, Lorenz and Zenga curves and related inequality indices. In addition to the well-known stochastic order based on Lorenz curve, the stochastic order based on Zenga curve is considered. Since the new generalized Weibull distribution seems to be suitable to model wealth, financial, actuarial and especially income distributions, these findings are fundamental in the understanding of how parameter values are related to inequality. Also, the estimation of parameters by maximum likelihood and moment methods is discussed. Finally, this distribution has been fitted to United States and Austrian income data sets and has been found to fit remarkably well in compare with the other widely used income models. 相似文献
13.
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
14.
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
15.
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
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18.
A. M. Abd El-Raheem 《Journal of Statistical Computation and Simulation》2019,89(16):3075-3104
The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion. 相似文献
19.
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
20.
Witkower Zachary Tracy Jessica L. Pun Anthea Baron Andrew S. 《Journal of Nonverbal Behavior》2021,45(4):505-518
Journal of Nonverbal Behavior - Past research has demonstrated that children understand distinct emotion concepts and can accurately recognize facial expressions of distinct emotions by a young... 相似文献