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831.
随着高等教育规模的扩大,学业表现不良逐渐成为一个不容忽视的现象,对学业表现不良的学生进行预测并提早给予干预可降低退学率并减少教育资源的损失。由于导致学业表现不良的因素众多且关系复杂,传统的基于相关分析的研究方法很难建立早期预测模型并进行应用。本研究旨在利用机器学习算法,对数据进行挖掘,并建立学业表现预测模型。研究对653名大一新生的心理健康状况、应对方式、人格、内外控倾向和相关人口统计学信息进行了收集,并在一年后采集了其学业成绩,利用随机森林(RF)、K邻近(KNN)、支持向量机(SVM)、决策树(DT)、朴素贝叶斯(NB)等机器学习算法建立了分类模型。结果显示,随机森林算法在识别学业表现不良学生时有最好的表现,其中准确率95.86%, 召回率91.83%,f1分数为93.80%。特征重要性分析显示,前10个对模型有最高贡献度的特征包括:年龄、性别、是否为独生子、内外控倾向、神经质倾向、积极应对倾向、宜人性倾向、一般症状指数、开放性倾向和焦虑水平。为避免过度拟合问题,本研究在一年后收集的166名新生样本中进行了模型验证,结果显示模型在新数据集上有较好的泛化表现,其中f1分数90.90%,准确率92.60%,召回率89.26%。研究提示基于人口统计学和心理测评信息,机器学习算法有助于及早识别学业表现不良学生并为开展早期干预提供启示。  相似文献   
832.
加工速度和工作记忆反应了不同的认知加工过程,在认知发展研究中,加工速度和工作记忆所起的作用仍存在较大的分歧.采用多因素混合实验设计,在严格控制条件下,比较了语文学习困难和控制组儿童的工作记忆和加工速度.结果发现,与控制组相比,语文学习困难儿童在工作记忆和加工速度方面均存在明显的不足,但加工速度不能解释不同能力组之间的差异,语文学习困难儿童的缺陷在于工作记忆能力的下降.工作记忆的缺陷在于言语工作记忆和中央执行功能的不足,与视空间工作记忆能力无关.语文学习困难既存在一般的工作记忆缺陷(中央执行功能)也存在特定的工作记忆(言语工作记忆)能力的不足.  相似文献   
833.
本研究采用5(学习次数)×2(材料难度)被试内设计,考察材料难度和学习次数对即刻和延迟学习判断绝对准确性的影响。45名大学生被试参加实验,共收集有效数据37个。结果表明:(1) 即刻条件下,高、低难度词对都出现了练习伴随低估效应;(2) 延迟条件下,高、低难度词对均未出现练习伴随低估效应。对低难度词对的学习判断准确预测了回忆成绩,高难度词对则出现了练习伴随高估效应;(3) 随着学习次数的增加,不同难度词对在即刻条件下的练习伴随低估效应趋于消失,延迟条件下高难度词对的练习伴随高估效应趋于消失。  相似文献   
834.
胡卫平  张淳俊 《心理学报》2007,39(4):697-705
采用科学领域的跨学科概念图创作任务, 探讨了跨学科概念图创作能力与科学创造力的关系。研究发现:(1)跨学科概念图创作能力与科学创造力显著正相关;(2)概念图创作的命题、交叉连接与创造力的流畅性、独创性、灵活性显著相关;交叉连接与独创性显著相关;(3)跨学科概念图创作能力的个体差异表现在科学创造力的各个方面。研究表明,跨学科概念图创作任务与科学创造力测验考察了学习者相似的心理能力;跨学科概念图创作不仅可以用于促进跨学科信息整合和知识建构,还可以作为理解学习者创造性思维能力的有效工具  相似文献   
835.
采用两个实验:实验一以陈述性知识为学习内容,实验二以程序性知识为学习内容,在这两种情况下,分别用组间设计探讨信息呈现方式对不同认知风格和空间能力的学习者在多媒体环境下学习效果的影响。结果表明:(1)认知风格对陈述性知识在多媒体环境下的学习效果产生影响,而选择的多媒体信息呈现方式和被试的空间能力则对其不产生影响;(2)对于程序性知识的保持,多媒体信息呈现方式和被试认知风格都会对学习效果产生影响,被试空间能力则不会产生影响,而且被试不同的认知风格在不同的多媒体信息呈现方式上会产生不同的影响;(3)对程序性知识的迁移,多媒体信息呈现方式、被试认知风格和空间能力都会对多媒体环境下的学习效果产生影响,而且被试不同的认知风格和空间能力在不同的多媒体信息呈现方式上都会产生不同的影响。  相似文献   
836.
333名初中生被分配到基于描述表征的两种条件下,分别对获得框架与损失框架下的风险回避类与风险寻求类学习时间选项进行抉择,以探讨信息外部表征对学习决策框架效应的影响.结果表明:1)在基于描述表征的条件下,学习决策领域中存在框架效应,但有其领域特殊性,被试在获得框架中无明显决策偏向,但在损失框架中的决策明显偏向风险寻求.2)在基于经验表征的条件下,学习决策不存在框架效应.无论是在获得框架还是损失框架中的学习决策均不存在明显的偏向.  相似文献   
837.
I investigated the differential effects of self-monitoring of attentional behavior and self-monitoring of productivity on on-task behavior and academic response rate. Subjects were four learning disabled children with significant attentional problems. Results indicated relatively equivalent increases in on-task behavior over baseline during all treatment phases. Academic response rate also improved under both interventions, with self-monitoring of productivity showing a superior effect for one subject, an equivalent effect for one subject, and less dear results for two subjects.  相似文献   
838.
The pace of change in the world is accelerating, yet educational institutions have not kept pace. Indeed, schools have historically been the most static of social institutions, uncritically passing down from generation to generation outmoded didactic, lecture-and-drill-based, models of instruction. Predictable results follow. Students, on the whole, do not learn how to work by, or think for, themselves. They do not learn how to gather, analyze, synthesize and assess information. They do not learn how to analyze the diverse logic of the questions and problems they face and hence how to adjust their thinking to those problems. They do not learn how to enter sympathetically into the thinking of others, nor how to deal rationally with conflicting points of view. They do not learn to become critical readers, writers, speakers and listeners. They do not learn how to use their native languages clearly, precisely, or persuasively. They do not, therefore, become literate, in the proper sense of the word. Neither do they gain much in the way of genuine knowledge since, for the most part, they could not explain the basis for what they believe. They would be hard pressed to explain, for example, which of their beliefs were based on rational assent and which on simple conformity to what they have been told. They have little sense as to how they might critically analyze their own experience, or identify national or group bias in their own thinking. They are much more apt to learn on the basis of irrational than rational modes of thought. They lack the traits of mind of a genuinely educated person: intellectual humility, courage, integrity, perseverance, and faith in reason.Happily, there is a movement in education today striving to address these problems in a global way, with strategies and materials for the modification of instruction at all levels of education. At its foundation is an emerging new theory of knowledge, learning, and literacy, one which recognizes the centrality of independent critical thinking to all substantial learning, one which recognizes that higher-order, multilogical thinking is as important to childhood as to adult learning, and as important to foundational learning in monological as in multilogical disciplines. This educational reform movement is not proposing an educational miracle cure, for its leading proponents recognize that many social and historical forces must come together before the ideals of the critical thinking movement will become a full academic reality. Schools do not exist in a social vacuum. To the extent that the broader society is uncritical so, on the whole, will be society's schools. Nevertheless, the social conditions necessary for fundamental changes in schooling are increasingly apparent. The pressure for fundamental change is growing. Whether and to what extent these needed basic changes will be delayed or side-tracked, thus requiring new periodic resurgences of this movement, with new, more elaborate articulations of its ideals, goals, and methods — only time will tell.  相似文献   
839.
The acute effects of cocaine hydrochloride (4 to 96 mg/70 kg) and alcohol (0 to 1.0 g/kg), administered alone and in combination, were assessed in two experiments with human volunteers responding under a multiple schedule of repeated acquisition and performance of response chains. Subjects were intermittent users of cocaine and regular drinkers who were not cocaine or alcohol dependent. Alcohol was mixed with orange juice and ingested in six drinks within 30 min; cocaine was administered intranasally 45 min after completion of drinking. In each component of the multiple schedule, subjects completed response sequences using three keys of a numeric keypad. In the acquisition component, a new sequence was learned each session. In the performance component, the response sequence always remained the same. Results were consistent in both experiments, despite variations in the order in which the drugs were tested alone and in combination. Alcohol administered alone increased overall percentage of errors and decreased rates of responding in the acquisition component, whereas responding in the performance component generally was unaffected. Cocaine administered alone decreased rates of responding but did not affect accuracy of responding in the acquisition component, and enhanced accuracy of responding without affecting rates of responding in the performance component. The combined doses of cocaine and alcohol attenuated the effects observed with alcohol and cocaine alone. These results suggest that, under the conditions investigated in this study, (a) alcohol produces greater behavioral disruption than cocaine or cocaine-alcohol combinations, (b) cocaine and alcohol each attenuate effects of the other, and (c) such attenuation is most pronounced for cocaine attenuating the disruptive effects of alcohol.  相似文献   
840.
樟柳碱所致学习和记忆障碍动物模型的探讨   总被引:2,自引:0,他引:2  
本实验采用水迷津法、步下法和步入法,用樟柳碱制备学习和记忆障碍的动物模型。结果表明,樟柳碱(10毫克/公斤)可使小鼠引起学习障碍,其表现为通过水迷津全程的时间延长,而且小鼠进入盲路的错误次数明显增多。樟柳碱(10毫克/公斤)可使小鼠引起记忆障碍,在樟柳碱的影响下,小鼠步下平台或步入暗箱的潜伏期明显缩短,并使它们的错误次数增多。本实验结果进一步表明,测定小鼠的记忆障碍,步入法似乎比步下法更为敏感。  相似文献   
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