中文文本抄袭检查技术的研究

该文介绍了一种基于字符串匹配的中文文本抄袭检测方法——k-grams算法,并指出了选取常用语句降低了其判别的准确性。提出了利用基于统计的中文分词技术实现对k-grams算法的改良。实验结果表明改良后的算法判断抄袭的准确性得到了提高。     

中文文本抄袭检查系统的改良与设计

由于目前常见的文本抄袭检查系统都存在对文本的关键信息选择不准确的问题,从而影响了判断的准确性。开发的中文文本抄袭检查系统在采用k-grams算法的基础上,利用基于统计的中文分词技术对其改良。实验结果表明通过改良可以使系统更有效地选取关键信息,提高判断的准确性。     

Industrial applications of formulation computations: Is the computer the enemy?

The basis of modern computations of colorant formulations is a 1931 article by Kubelka and Munk. Virtually all the subsequent important contributions to the problem were published in the following four decades; if it were the practice for software instructions to include a comprehensive list of published references, it is unlikely that many, if any, would be dated later than the advent of the modern computer. This implies either that no major problems remain unsolved, or that some factor is discouraging further improvements or is inhibiting their publication. This leads to the hypothesis that the accepted practice, in the dissemination of computer documentation, of failing to provide references to relevant published work is a significant basis of stultifying new development. It is accordingly urged that promulgators of software accept the responsibility, universally observed in scientific and technological publication, of disclosing prior work by supplying appropriate lists of relevant published material. The failure to disclose prior published work should be deemed a form of plagiarism. © 1996 John Wiley & Sons, Inc.     

An extension of the FFT‐based algorithm for the match‐count problem to weighted scores

The match‐count problem on strings is the basic problem of counting the matches of characters between two strings for every possible alignment. The problem is classically computed in O (σ n log m ) time using a fast Fourier transform (FFT) for two strings of lengths m and n (m ≤ n ) over an alphabet of size σ . This paper extends the target of this FFT‐based algorithm to a weighted version of the problem, which computes the sum of similarities between characters instead of the number of matches. The algorithm extended in this paper can solve the weighted match‐count problem in O (dn log m ) time by mapping characters to numerical vectors of dimensionality d . This paper also evaluates the usefulness of the extended algorithm by applying it to plagiarism detection in documents. The experimental results show that the proposed algorithm is applicable to general vector representation of words and that the obtained plagiarism detection method can extremely reduce the processing time with a slight decrease of accuracy from the method based on the normal match‐count problem.     

Recognizing authors: an examination of the consistent programmer hypothesis

Software developers have individual styles of programming. This paper empirically examines the validity of the consistent programmer hypothesis: that a facet or set of facets exist that can be used to recognize the author of a given program based on programming style. The paper further postulates that the programming style means that different test strategies work better for some programmers (or programming styles) than for others. For example, all‐edges adequate tests may detect faults for programs written by Programmer A better than for those written by Programmer B. This has several useful applications: to help detect plagiarism/copyright violation of source code, to help improve the practical application of software testing, and to help pursue specific rogue programmers of malicious code and source code viruses. This paper investigates this concept by experimentally examining whether particular facets of the program can be used to identify programmers and whether testing strategies can be reasonably associated with specific programmers. Copyright © 2009 John Wiley & Sons, Ltd.     

Identifying and profiling scholastic cheaters: Their personality, cognitive ability, and motivation.

Despite much research, skepticism remains over the possibility of profiling scholastic cheaters. However, several relevant predictor variables and newer diagnostic tools have been overlooked. We remedy this deficit with a series of three studies. Study 1 was a large-scale survey of a broad range of personality predictors of self-reported cheating. Significant predictors included the Dark Triad (Machiavellianism, narcissism, psychopathy) as well as low agreeableness and low conscientiousness. Only psychopathy remained significant in a multiple regression. Study 2 replicated this pattern using a naturalistic, behavioral indicator of cheating, namely, plagiarism as indexed by the Internet service Turn-It-In. Poor verbal ability was also an independent predictor. Study 3 examined possible motivational mediators of the association between psychopathy and cheating. Unrestrained achievement and moral inhibition were successful mediators whereas fear of punishment was not. Practical implications for researchers and educators are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

面向代码相似度检测的指纹选取方法

代码相似度检测是代码抄袭检测的核心组成部分,对于营造良好的学习氛围、提高知识产权保护意识具有重要作用。总结了应用指纹技术检测代码相似度的基本思路,分析了几种常见的指纹选取方法的优缺点,提出一种改进的面向代码相似度检测的指纹选取方法。该方法能够从疑似抄袭代码集中去除由代码编写规则产生的虚假相似代码对,有效获得代码之间准确的相似度值。     

基于多种技术的混合式程序代码抄袭检测方法

在分析现有程序代码抄袭检测系统的特点及局限性的基础上,提出一种综合文本分析、结构度量和属性计数技术的混合式程序抄袭检测方法。应用文档指纹技术和Winnowing算法计算程序的文本相似度;将程序代码表示成动态控制结构树（Dynamic Control Structure tree,DCS）,运用Winnowing算法计算DCS树相似度,从而得到结构相似度;收集并统计程序中的每个变量信息,应用变量相似度算法分析变量信息节点获取变量相似度;分别赋予文本相似度、结构相似度和变量相似度一个权值,计算得到总体的代码相似度。实验结果表明,所提出的方法能够有效检测出各种抄袭行为。针对不同的抄袭门槛值,使用该方法的检测结果准确度和查全率高于JPLAG系统。特别对于结构简单的程序组,此方法和JPLAG系统检测结果的平均准确度分别为82.5%和69.5%,说明所提的方法更加有效。     

基于斜率密度聚类的相似文本标定

相似文本标定是抄袭检测的一个重要环节,现有标定方法大多采用直接对文本或指纹进行合并的方式,标定精度受干扰信息影响较大。针对这种局限性,分析了匹配指纹对的语义特征,提出基于斜率密度的相似文本聚类方法,将文本匹配合并问题转化成稠密样本点聚类问题,并在PAN公用语料库上对该方法进行了测试,得到的主要指标优于PAN10前3名。目前已将该方法用于华南理工大学特色专业教学平台的作业查抄,取得了较好的效果。     

Source credibility and idea improvement have independent effects on unconscious plagiarism errors in recall and generate-new tasks.

Unconscious plagiarism occurs when people try to generate new ideas or when they try to recall their own ideas from among a set generated by a group. In this study, the factors that independently influence these two forms of plagiarism error were examined. Participants initially generated solutions to real-world problems in 2 domains of knowledge in collaboration with a confederate presented as an expert in 1 domain. Subsequently, the participant generated improvements to half of the ideas from each person. Participants returned 1 day later to recall either their own ideas or their partner's ideas and to complete a generate-new task. A double dissociation was observed. Generate-new plagiarism was driven by partner expertise but not by idea improvement, whereas recall plagiarism was driven by improvement but not expertise. This improvement effect on recall plagiarism was seen for the recall-own but not the recall-partner task, suggesting that the increase in recall-own plagiarism is due to mistaken idea ownership, not source confusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)