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101.
Sven Trenholm Lara Alcock Carol Robinson 《International Journal of Mathematical Education in Science & Technology》2013,44(8):1197-1221
Research suggests it is difficult to learn mathematics in the fully asynchronous online (FAO) instructional modality, yet little is known about associated teaching and assessment practices. In this study, we investigate FAO mathematics assessment and feedback practices in particular consideration of both claims and findings that these practices have a powerful influence on learning.A survey questionnaire was constructed and completed by 70 FAO undergraduate mathematics instructors, mostly from the USA, who were each asked to detail their assessment and feedback practices in a single FAO mathematics course. Alongside these questions, participants also answered the 16-item version of the Approaches to Teaching Inventory. In addition, a novel feedback framework was also created and used to examine how feedback practices may be related to participants' approaches to teaching.Results show that assessment and feedback practices are varied and complex: in particular, we found there was not a simple emphasis on summative assessment instruments, nor a concomitant expectation these would always be invigilated. Though richer assessment feedback appears to be emphasized, evidence suggests this feedback may not be primarily directed at advancing student learning. Moreover, we found evidence of a reliance on computer--human interactions (e.g. via computer-assisted assessment systems) and further evidence of a decline in human interactions, suggesting a dynamic that is both consistent with current online learning theory and claims FAO mathematics courses are becoming commodified. Several avenues for further research are suggested. 相似文献
102.
Abstract Population features inferred from single‐species, age‐structured models are compared to those inferred from a multispecies, age‐structured model that includes predator‐prey interactions among three commercially harvested fish species—walleye pollock, Atka mackerel, and Pacific cod—on the Aleutian Shelf, Alaska. The multispecies framework treats the single‐species models and data as a special case of the multispecies model and data. The same data from fisheries and surveys are used to estimate model parameters for both single‐species and multispecies configurations of the model. Additionally, data from stomach samples and predator rations are used to estimate the parameters of the multispecies model. One form of the feeding functional response, predator pre‐emption, was selected using AIC from seven alternative models for how the predation rate changes with the densities of prey and possibly other predators. Differences in estimated population dynamics and productivity between the multispecies and single‐species models were observed. The multispecies model estimated lower mackerel population sizes from 1964–2003 than the single‐species model, while the spawning biomass of pollock was estimated to have declined more than three times faster since 1964 by the multispecies model. The variances around the estimates of spawning biomass were smaller for mackerel and larger for pollock in the multispecies model compared to the single‐species model. 相似文献
103.
针对目前指标体系在构建和评价方面缺乏统一理论与方法这一现状,在不考虑具体评价问题的基础上,对一般意义上的指标体系进行了构建原理与评价方法研究.从时间维、方法维和逻辑维三方面对构建方法进行了阐述;建立了指标体系的数学模型,并提出了基于正交实验设计的指标权重计算方法;以合理指标体系的基本要素为依据,定量地分析了体系的完备性和指标间的相关性. 相似文献
104.
运用对偶标度统计方法计算儿童发展调查问题中原始数据的变量权和样本得分,从而确定评价因素集.采用多层前馈模糊神经网络——FM LP实现对儿童个体综合素质的定量评价. 相似文献
105.
敌情威胁程度的判断是定下作战决心的基础.提出利用多级模糊综合评判的方法,首先利用层次分析法(AHP法)综合专家的判断,建立权重集,然后利用模糊综合评判理论对对战场某一指定区域的模糊敌情进行威胁程度判断,从而将两种方法的优点综合起来.并给出了一个应用该方法的海区模糊敌情判断实例,结论说明该方法可行. 相似文献
106.
Hironori Fukukawa Theodore J. Mock 《International Journal of Approximate Reasoning》2012,53(2):190-199
This paper examines possible differences in auditors’ performance when they make belief-based versus probability-based risk assessments by focusing on two phases of the financial statement audit process: the assessment of two attributes of audit evidence (‘strength’ and ‘direction’) and the aggregation of evidence. Based on an experiment in which 48 experienced auditors participated, three important findings were observed. First, there was no significant difference in the mean assessment of strength of evidence measured using the likelihood ratio. However, the difference in the assessed direction of evidence, that is whether the evidence is interpreted as being confirming or disconfirming, is significant for one of the cases examined. This result shows that auditors making belief-based assessments are able to assess the direction of the evidence more accurately than auditors making probability-based assessments. Third, the auditors’ aggregation of evidence was not in accordance with ‘AND’ logic for either auditors making belief-based or probability-based assessments. These empirical results raise issues which need to be addressed in practice and in future research. 相似文献
107.
In this paper, we study the bivariate lognormal distribution from a reliability point of view. The conditional distribution of X given Y > y is found to be log‐skew normal. The monotonicity of the hazard rates of the univariate as well as the conditional distributions is discussed. Clayton's association measure is obtained in terms of the hazard gradient, and its value in the case of our model is derived. The probability distributions, in the case of series and parallel systems, are derived, and the monotonicity of their failure rates is discussed. Three real applications of the bivariate lognormal distribution are provided, two from financial economics and one from reliability. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
108.
本文对存在的不对称信息的环境下的具有私人信息道德风险的委托—代理人模型的合约问题进行了详细的讨论,并得出一些有新意的结论.此讨论问题的方法很值得推荐和推广,特别是在最优激励合同中,比如投资激励,管理机制中的激励,销售激励,保险激励等合同的设计,都可以借鉴此方法来研究和分析. 相似文献
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