Retrieving and classifying instances of source code plagiarism     

Debasis?GangulyEmail authorView author&#;s OrcID profile  Gareth?J.?F.?Jones  Aarón?Ramírez-de-la-Cruz  Gabriela?Ramírez-de-la-Rosa  Esaú?Villatoro-Tello 《Information Retrieval》2018,21(1):1-23

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.  相似文献   

An Investigation of Textbook Vetting and Evaluation Process in Tanzania     

Daniel C. Rotich  Emily J. Kogos  Zamda R. Geuza 《Publishing Research Quarterly》2018,34(1):96-109

Textbook vetting and evaluation process intends to ensure that the materials provided are relevant, of the required quality, suitable ad would enhance learning efficiency and effectiveness. The paper investigates the role of publishers and Tanzania Institute of Education (TIE) in the textbooks vetting and evaluation process; examines factors used to vet, evaluate and approve primary and secondary school textbooks in Tanzania and proposes Strategies that would enhance the textbook vetting, evaluation and process. The study used a mixed method research design. Respondents were selected educational publishers; MoEVT, Baraza la Kiswahili Tanzania, TIE, and Publishers Association of Tanzania. Questionnaire and semi- structured interview were used to collect data which were analysed qualitatively and quantitatively. Major findings of the study were; textbooks vetting and evaluation process is not professionally conducted although standard criteria have been established; there is not well established roles among key players involved in the vetting and evaluation process leading to conflict of interest between TIE and the publishers. The study recommends establishing an independent professional evaluation board and a well-defined timetable and effective communication among various players; enacting a book policy and adopting a limited multiple-textbook publishing system.  相似文献   

Editorial     

Daniel M. Pennell 《Slavic & East European Information Resources》2018,19(1-2):1-2

  相似文献   

Applying LDA Topic Modeling in Communication Research: Toward a Valid and Reliable Methodology     

Daniel Maier  A. Waldherr  P. Miltner  G. Wiedemann  A. Niekler  A. Keinert 《Communication methods and measures》2018,12(2-3):93-118

ABSTRACT

Latent Dirichlet allocation (LDA) topic models are increasingly being used in communication research. Yet, questions regarding reliability and validity of the approach have received little attention thus far. In applying LDA to textual data, researchers need to tackle at least four major challenges that affect these criteria: (a) appropriate pre-processing of the text collection; (b) adequate selection of model parameters, including the number of topics to be generated; (c) evaluation of the model’s reliability; and (d) the process of validly interpreting the resulting topics. We review the research literature dealing with these questions and propose a methodology that approaches these challenges. Our overall goal is to make LDA topic modeling more accessible to communication researchers and to ensure compliance with disciplinary standards. Consequently, we develop a brief hands-on user guide for applying LDA topic modeling. We demonstrate the value of our approach with empirical data from an ongoing research project.  相似文献   

Technological research in the EU is less efficient than the world average. EU research policy risks Europeans’ future     

Alonso Rodríguez-Navarro  Ricardo Brito 《Journal of Informetrics》2018,12(3):718-731

We have studied the efficiency of research in the EU by a percentile-based citation approach that analyzes the distribution of country papers among the world papers. Going up in the citation scale, the frequency of papers from efficient countries increases while the frequency from inefficient countries decreases. In the percentile-based approach, this trend, which is uniform at any citation level, is measured by the e_p index that equals the P_{top 1%}/P_{top 10%} ratio. By using the e_p index we demonstrate that EU research on fast-evolving technological topics is less efficient than the world average and that the EU is far from being able to compete with the most advanced countries. The e_p index also shows that the USA is well ahead of the EU in both fast- and slow-evolving technologies, which suggests that the advantage of the USA over the EU in innovation is due to low research efficiency in the EU. In accord with some previous studies, our results show that the European Commission’s ongoing claims about the excellence of EU research are based on a wrong diagnosis. The EU must focus its research policy on the improvement of its inefficient research. Otherwise, the future of Europeans is at risk.  相似文献   

<Emphasis Type="Bold">Heidegger’s Wrong Turn</Emphasis>     

Daniel Bonevac 《Academic Questions》2017,30(3):302-320

  相似文献   

The relative age effect on physical fitness in preschool children     

Rocío Cupeiro  Miguel A. Rojo-Tirado  Cristina Cadenas-Sanchez  Enrique G. Artero  Ana B. Peinado  Idoia Labayen 《Journal of sports sciences》2020,38(13):1506-1515

ABSTRACT

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ λ = 0.383; F_10,5996 = 369.64; p < 0.001, η_p ² = 0.381) and of quarter (Wilks’ λ = 0.874; F_15,8276.6 = 27.67; p < 0.001; η_p ² = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers.  相似文献   

Academe’s House Divided     

Daniel B. Klein 《Academic Questions》2011,24(3):365-370

  相似文献   

Decoding general relativity     

Daniel Kennefick 《Metascience》2011,20(1):91-93

  相似文献   

One step antibody-mediated isolation and patterning of multiple cell types in microfluidic devices     

Danny Bavli  Elishai Ezra  Daniel Kitsberg  Margarita Vosk-Artzi  Shashi K. Murthy  Yaakov Nahmias 《Biomicrofluidics》2016,10(2)

Cell-cell interactions play a key role in regeneration, differentiation, and basic tissue function taking place under physiological shear forces. However, current solutions to mimic such interactions by micro-patterning cells within microfluidic devices have low resolution, high fabrication complexity, and are limited to one or two cell types. Here, we present a microfluidic platform capable of laminar patterning of any biotin-labeled peptide using streptavidin-based surface chemistry. The design permits the generation of arbitrary cell patterns from heterogeneous mixtures in microfluidic devices. We demonstrate the robust co-patterning of α-CD24, α-ASGPR-1, and α-Tie2 antibodies for rapid isolation and co-patterning of mixtures of hepatocytes and endothelial cells. In addition to one-step isolation and patterning, our design permits step-wise patterning of multiple cell types and empty spaces to create complex cellular geometries in vitro. In conclusion, we developed a microfluidic device that permits the generation of perfusable tissue-like patterns in microfluidic devices by directly injecting complex cell mixtures such as differentiated stem cells or tissue digests with minimal sample preparation.  相似文献