Retrieving and classifying instances of source code plagiarism

Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.     

Structural and convergent validity of the homework performance questionnaire

Homework is a requirement for most school-age children, but research on the benefits and drawbacks of homework is limited by lack of psychometrically sound measurement of homework performance. This study examined the structural and convergent validity of scores from the newly developed Homework Performance Questionnaire – Teacher Scale (HPQ-T). Participants were 112 teachers of 224 students in six Illinois school districts. Common factor analysis with principal axis extraction and promax rotation was used for data analysis. Results revealed three salient factors: Parent support, student competence and homework completion. Subsequently, convergent validity of HPQ-T subscale scores with subscale scores from the Learning Behaviours Scale was examined. Findings suggest that the HPQ-T may potentially be a useful tool for improving research on homework and identifying strengths and weaknesses in student homework performance. However, modifications are recommended to optimise the utility of the scores.     

Developing a student-led school mental health strategy

Although there is increasing interest in promoting mental health and wellbeing within education, to date, the voices of young people appear to have been almost completely overlooked in the development of school-based mental health practices. This is despite increasing focus on young people’s participation; and the fact that young people may be best positioned to understand the pressures of contemporary society. This paper, co-authored by educational psychologists (EPs), school students and the school vice-principal, documents the development of a student-led mental health initiative within a high-achieving girls’ grammar school, led by students aged 12–18. Following EP input, the students devised a whole-school, student-friendly mental health strategy with the support of the EPs and senior school staff. As the project progressed, it became evident that applying even carefully selected adult mental health models to school contexts might not be appropriate; instead the students advocated for young person-friendly, innovative, contemporary and creative ways of communicating information about mental health, which avoided stigma. The students involved were well-placed to identify environmental stressors and to disseminate their strategy. The authors conclude that mental health planning in schools should encourage greater student participation, show caution over applying adult mental health models and promote greater use of technology or visual resources.     

TRANSITION TO SCHOOL: THE EXPERIENCES OF CANADIAN AND IMMIGRANT FAMILIES OF CHILDREN WITH AUTISM SPECTRUM DISORDERS

Transition to school for children with autism spectrum disorders (ASDs) places demands on children, parents, and school settings. The unique experiences of parents from diverse backgrounds have not been studied extensively. This qualitative study explored the experiences of 5 Canadian and 5 immigrant families during the transition to school for their children with ASDs. Parent perceptions of support systems during this transition and their experiences with preschool and elementary school staff were analyzed to understand their experiences. Thematic analyses of parent interviews revealed that parents perceived the quality of care during preschool as more supportive than the care received in elementary school. A variety of resources, such as familial, educational, and community support, seemed to help some Canadian and immigrant families in different ways. The transition to school experiences of parents of children with ASDs has important implications for school psychologists who facilitate and mediate parent–school partnerships and interagency collaboration.     

反季节冬春蔬菜种植农民收益的初步分析——保山市隆阳区潞江坝的实证研究

本文初步对保山市反季节蔬菜进行分析,纵向从蔬菜种子的来源、蔬菜的栽培、蔬菜的收集销售、贮藏和运输这一商品链出发,逐级分析菜农、蔬菜收集人、菜老板的收益分析,从而在整体上揭示菜农在这条商品链上的收益地位;横向同种植其他经济作物,如香烟和甘蔗的收益作对比分析。说明了西部民族山区的广大农户主要收入来源于种植业的现实,农户如何选择种植的经济作物对提高收入有直接的影响,决定农户种植收益除了市场的因素以外各级政府的行政行为则也起到一定的作用。     

A Dialogic Path to Evidence-Based Argumentive Writing

Central to argument are evidence-based claims, requiring coordination of a claim with evidence bearing on it. We advocate a dialogic approach to developing argument skills and in the work reported here examine the further scaffold of prompts that exemplify functions of evidence in relation to a claim. This scaffold was successful in accelerating the prevalence of evidence-based claims in essays of low-performing middle schoolers compared to participants in the same year-long dialog-based intervention who received no or a limited form of evidence prompts and compared to previous samples engaged in a nondialogic curriculum. An experimental group achieved a proportion of evidence-based claims above 50% by the end of the year, transferring their newly developing skill from one topic to another. The use of different types of evidence emerged in a sequence corresponding to the cognitive demands they posed. Students first used support-own evidence. They used weaken-other evidence increasingly over time, but the two evidence types inconsistent with their position (support-other and weaken-own) showed lesser and later gains. Supporting a dialogic approach, qualitative data showed that evidence use occurred most readily in dialogs; then in individual writing on the same topic; and to a more limited extent in essays on a new, unstudied topic.     

Data Mining to Combat Terrorism and the Roots of Privacy Concerns

Recently, there has been a heavy debate in the US about the government’s use of data mining in its fight against terrorism. Privacy concerns in fact led the Congress to terminate the funding of TIA, a program for advanced information technology to be used in the combat of terrorism. The arguments put forward in this debate, more specifically those found in the main report and minority report by the TAPAC established by the Secretary of Defense to examine the TIA issue, will be analysed to trace the deeper roots of this controversy. This analysis will in turn be used as a test case to examine the adequacy of the usual theoretical frameworks for these kinds of issues, in particular the notion of privacy. Whereas the dominant theoretical framing of the notion of privacy turns around access to information, most of the core arguments in the debate do not fit in this kind of framework. The basic disagreements in the controversy are not about mere access, they involve both access and use. Furthermore, whereas the issue of access by itself refers to a more or less static situation, the real disagreements much more concern the organisational dynamics of the use of information, the mechanisms in the organisation that control these dynamics, and the awareness present within the organisation of the ‘social risks’ these dynamics represent. The bottom line question is whether the assessment of these gives sufficient reason for trust.     

Japanese Conceptions of Privacy: An Intercultural Perspective

This paper deals with intercultural aspects of privacy, particularly with regard to important differences between Japanese and the Western views. This paper is based on our discussions with Rafael Capurro – a dialogue now represented by two separate but closely interrelated articles. The companion paper is broadly focused on the cultural and historical backgrounds of the concepts of privacy and individualism in “Western” worlds; our main theme focuses on different concepts of privacy in Japan and their sources in related aspects of Japanese culture. The interrelationship between our two papers is apparent in our taking up identical or similar topics in each paper. Reading our two papers in conjunction with each other will bring about deeper and broader insights into the diverse values and worldviews of Japan and Western cultures that underlie concepts of privacy that at a surface level appear to be similar     

Examining Reasoning Practices and Epistemic Actions to Explore Students’ Understanding of Genetics and Evolution

Science & Education - This article focuses on students’ discursive moves and reasoning practices while engaged in a task that requires making explanatory links between sickle cell disease...