择校学生能否影响非择校生的学业表现？——来自随机分班数据的经验证据

文章使用中国教育追踪调查基线数据（2013—2014学年）中的随机分班样本,详细讨论了班级择校学生比例与非择校生学业发展之间的关系。结果显示,班级择校学生比例增加将直接降低非择校生工作日和周末的学业投入水平,进而引发非择校生学业成绩的下降。异质性分析表明,首先,班级择校学生比例增加主要降低非择校生的英语成绩;其次,班级择校学生比例增加主要降低男性非择校生的学业成绩;再次,择校学生与非择校生相处时间越长,择校学生对非择校生学业发展的阻碍作用将愈加明显;最后,与“以房择校”相比,班级内通过“权钱并施”方式就读的学生比例增加更不利于非择校生的学业发展。文章由择校的同伴效应视角切入,为贯彻落实义务教育阶段“就近入学”政策提供新的经验证据。     

Integrating digital literacies and scientific communication in a multimedia anatomy group assignment to advance contextual learning

Anatomists are facing a new generation of learners who will study and work in a technology-rich environment. Indeed, digital technologies are tremendously changing how information and knowledge are communicated and retrieved. However, it remains unclear whether an anatomy assessment can be designed to promote contextual learning through integrating a digital communication strategy. To investigate this, assessment methods were diversified in the first-year neuroanatomy and third-year regional anatomy curricula through implementing a multimedia human anatomy group assignment integrating digital literacies and scientific communication. Through completing this multimedia assignment, students demonstrated their anatomy knowledge transfer using a range of approaches. The main mode of presentations chosen in the two anatomy units were non-animated video presentations (~50%), animated video presentations (~30%), storyboards (~10%), podcasts (~3%), and filmed videos (~3%). A 5-point Likert scale learning and teaching survey was conducted for a total of 195 undergraduate health science students to evaluate students' perception of this group assignment. The majority of students (70–80%) strongly agreed or agreed that the multimedia group assignment helped their teamwork skills. Students who produced animated videos significantly outperformed those who adopted the non-animated presentations during the end-of-semester theory examination (p < 0.05). This study demonstrates that an anatomy group assignment integrating digital literacy and scientific communication is an effective assessment strategy associated with a positive learning experience and outcome. This inquiry-based assignment promotes learning through assessment, allowing students to not only consolidate and extend anatomy knowledge but also developing effective digital communication skills, providing new insights into non-didactic anatomy assessments.     

离散型随机变量的统计规律性研究

随机变量的统计规律是一个复杂的概念。通过对典型实例的分析研究,揭示出一维离散型随机变量的形成过程及其变化规律。具体描述了样本点与随机变量之间的对应关系及事件与随机变量取值之间的等价关系,得出掷硬币正面出现的“总次数”近似服从正态分布,据此可刻划“掷硬币正面出现”这一随机现象的统计规律性．     

Fair and Explainable Depression Detection in Social Media

Detection at an early stage is vital for the diagnosis of the majority of critical illnesses and is the same for identifying people suffering from depression. Nowadays, a number of researches have been done successfully to identify depressed persons based on their social media postings. However, an unexpected bias has been observed in these studies, which can be due to various factors like unequal data distribution. In this paper, the imbalance found in terms of participation in the various age groups and demographics is normalized using the one-shot decision approach. Further, we present an ensemble model combining SVM and KNN with the intrinsic explainability in conjunction with noisy label correction approaches, offering an innovative solution to the problem of distinguishing between depression symptoms and suicidal ideas. We achieved a final classification accuracy of 98.05%, with the proposed ensemble model ensuring that the data classification is not biased in any manner.