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861.
Stephanie N. Seiler Ph.D. Bradley J. Brummel Ph.D. Kerri L. Anderson M.H.R.I.R. Kyoung Jin Kim Ph.D. Serena Wee Ph.D. C. K. Gunsalus J.D. 《Accountability in research》2013,20(4):217-246
We describe the summative assessment of role-play scenarios that we previously developed to teach central topics in the responsible conduct of research (RCR) to graduate students in science and engineering. Interviews with role-play participants, with participants in a case discussion training session, and with untrained students suggested that role-playing might promote a deeper appreciation of RCR by shifting the focus away from wanting to simply “know the rules.” We also present the results of a think-aloud case analysis study and describe the development of a behaviorally-anchored rating scale (BARS) to assess participants' case analysis performance. 相似文献
862.
E. Shirazi H. Doosti H.A. Niroumand N. Hosseinioun 《Journal of statistical planning and inference》2013
Here we consider wavelet-based identification and estimation of a censored nonparametric regression model via block thresholding methods and investigate their asymptotic convergence rates. We show that these estimators, based on block thresholding of empirical wavelet coefficients, achieve optimal convergence rates over a large range of Besov function classes, and in particular enjoy those rates without the extraneous logarithmic penalties that are usually suffered by term-by-term thresholding methods. This work is extension of results in Li et al. (2008). The performance of proposed estimator is investigated by a numerical study. 相似文献
863.
864.
S. H. Ong 《Statistics》2013,47(4):403-411
We consider two-sided Bayesian tolerance intervals, with approximate frequentist validity, for a future observation in balanced one-way and two-way nested random effects models. Probability matching conditions, specific to this problem, are derived in either case via a technique that involves inversion of approximate posterior characteristic functions. In addition to yielding probability matching priors for the present problem, these conditions are useful in evaluating certain other priors that have received attention in the literature. 相似文献
865.
论大学英语写作教学原则 总被引:3,自引:0,他引:3
聂龙 《浙江师范大学学报(社会科学版)》2000,(6)
本文着重探讨写作与批评性阅读之间的关系 ,认为在写作教学中通过批评性阅读培养学生的批评性语言意识是提高他们写作能力的一条重要原则。 相似文献
866.
朱志勇 《宝鸡文理学院学报(社会科学版)》1999,(3)
思维运动主体不是人脑,而是从事社会实践的人。近代形而上学唯物主义把人脑看作是思维运动的主体,虽然肯定了思维运动主体的物质性,但却忽视了它的社会实践性。马克思主义哲学从实践出发理解现存世界和人的思维,把实践看作“人的思维的最本质和最切近的基础”,将从事社会实践活动的人确立为思维运动的主体,从而在思维运动主体上实现了物质性、实践性和社会性三者的有机统一。 相似文献
867.
In pest risk assessment it is frequently necessary to make management decisions regarding emerging threats under severe uncertainty. Although risk maps provide useful decision support for invasive alien species, they rarely address knowledge gaps associated with the underlying risk model or how they may change the risk estimates. Failure to recognize uncertainty leads to risk‐ignorant decisions and miscalculation of expected impacts as well as the costs required to minimize these impacts. Here we use the information gap concept to evaluate the robustness of risk maps to uncertainties in key assumptions about an invading organism. We generate risk maps with a spatial model of invasion that simulates potential entries of an invasive pest via international marine shipments, their spread through a landscape, and establishment on a susceptible host. In particular, we focus on the question of how much uncertainty in risk model assumptions can be tolerated before the risk map loses its value. We outline this approach with an example of a forest pest recently detected in North America, Sirex noctilio Fabricius. The results provide a spatial representation of the robustness of predictions of S. noctilio invasion risk to uncertainty and show major geographic hotspots where the consideration of uncertainty in model parameters may change management decisions about a new invasive pest. We then illustrate how the dependency between the extent of uncertainties and the degree of robustness of a risk map can be used to select a surveillance network design that is most robust to knowledge gaps about the pest. 相似文献
868.
By using the theory of the second-order regular variation, we study the rates of the weak convergence of the maximum order
statistics under power normalization. The exact rates are obtained in the uniform metric and the total variation metric. The
relationship between the rates of convergence under linear and under power normalization is derived. Some illustrative examples
are given for comparing the rates of convergence. 相似文献
869.
The Freshwater Invertebrate Invasiveness Scoring Kit (FI‐ISK) is proposed as a screening tool for identifying potentially invasive freshwater invertebrates. FI‐ISK was adapted from the Fish Invasiveness Scoring Kit (FISK) of Copp, Garthwaite, and Gozlan, which is an adapted form of the Weed Risk Assessment (WRA) of Pheloung, Williams, and Halloy. Initial assessments using FI‐ISK, which include confidence (certainty/uncertainty) rankings by the assessor to each response, were calibrated to determine the most appropriate score thresholds for classifying nonnative species into low‐, medium‐, and high‐risk categories, using both the original medium‐to‐high risk threshold scores for the WRA (i.e., ≥6) and for FISK (i.e., ≥19). Patterns of the assessor's confidence, when making the responses during the FI‐ISK assessments, were also examined. Using receiver operating characteristic (ROC) curves, FI‐ISK was shown to distinguish accurately (and with statistical confidence) between potentially invasive and noninvasive species of nonnative crayfish (Decapoda: Astacidae, Cambaridae, Parastacidae), with the statistically appropriate threshold score for high‐risk species scores being ≥16. FI‐ISK represents a useful and viable tool to aid decision‐ and policymakers in assessing and classifying freshwater invertebrates according to their potential invasiveness. 相似文献
870.
H. Luke Shaefer Xiaoqing Song Trina R. Williams Shanks 《Review of Economics of the Household》2013,11(4):659-680
The Earned Income Tax Credit (EITC) is a refundable credit for low-income workers mainly targeted at families with children. This study uses the Survey of Income and Program Participation’s topical modules on Assets and Liabilities to examine associations between the EITC expansions during the early 1990s and the unsecured debt of the households of single mothers. We use two difference-in-differences comparisons over the study period 1988–1999, first comparing single mothers to single childless women, and then comparing single mothers with two or more children to single mothers with exactly one child. In both cases we find that the EITC expansions are associated with a relative decline in the unsecured debt of affected households of single mothers. While not direct evidence of a causal relationship, this is suggestive evidence that single mothers may have used part of their EITC to limit the growth of their unsecured debt during this period. 相似文献