Native language identification (NLID) for forensic authorship analysis of weblogs

This chapter introduces Native Language Identification (NLID) and considers the casework applications with regard to authorship analysis of online material. It presents findings from research identifying which linguistic features were the best indicators of native (L1) Persian speakers blogging in English, and analyses how these features cope at distinguishing between native influences from languages that are linguistically and culturally related. The first chapter section outlines the area of Native Language Identification, and demonstrates its potential for application through a discussion of relevant case history. The next section discusses a development of methodology for identifying influence from L1 Persian in an anonymous blog author, and presents findings. The third part discusses the application of these features to casework situations as well as how the features identified can form an easily applicable model and demonstrates the application of this to casework. The research presented in this chapter can be considered a case study for the wider potential application of NLID.

Comparing sentence-level features for authorship analysis in Portuguese

In this paper we compare the robustness of several types of stylistic markers to help discriminate authorship at sentence level. We train a SVM-based classifier using each set of features separately and perform sentence-level authorship analysis over corpus of editorials published in a Portuguese quality newspaper. Results show that features based on POS information, punctuation and word / sentence length contribute to a more robust sentence-level authorship analysis. © Springer-Verlag Berlin Heidelberg 2010.

Introducción

Sexualidad y Escritura (1850-2000) is a collection of thirteen essays which focus on the complex relationship between gender and writing in Spain from 1850 to 2000. This collection aims to provide a specifically Spanish cultural and historical context to the study of gender and writing and to challenge the effectiveness and validity of applying and adapting some feminist theory (based mainly in French and Anglo literary traditions) to works by both male and female Spanish writers. The introduction sets the tone of the essays it contains by discussing the Gilbert and Guar’s concept of female authors anxiety of authorship, and the reasons why their notions of the male dominated writing profession does not necessarily apply to Spanish literature of the nineteenth century in particular. The notable presence and success of female writers during the Romantic period and the way in which they in effect managed to feminize the writing profession illustrates how very different the Spanish literary context is from French, English or American models. The editors state that, rather than needing to work up the courage to take up the pen and publish their works, the issue facing Spanish women writers during parts of the last 150 years has been how to either maintain or regain their authorial voice and their place in letters, fighting to keep their heads above the rising and falling tides of literary trends.

Author identification, idiolect and linguistic uniqueness

For forty years linguists have talked about idiolect and the uniqueness of individual utterances. This article explores how far these two concepts can be used to answer certain questions about the authorship of written documents—for instance how similar can two student essays be before one begins to suspect plagiarism? The article examines two ways of measuring similarity: the proportion of shared vocabulary and the number and length of shared phrases, and illustrates with examples drawn from both actual criminal court cases and incidents of student plagiarism. The article ends by engaging with Solan and Tiersma's contribution to this volume and considering whether such forensic linguistic evidence would be acceptable in American courts as well as how it might successfully be presented to a lay audience.

“I didn’t mean to steal someone else’s words!”:a forensic linguistic approach to detecting intentional plagiarism

The concept of plagiarism is not uncommonly associated with the concept of intellectual property, both for historical and legal reasons: the approach to the ownership of ‘moral’, nonmaterial goods has evolved to the right to individual property, and consequently a need was raised to establish a legal framework to cope with the infringement of those rights. The solution to plagiarism therefore falls most often under two categories: ethical and legal. On the ethical side, education and intercultural studies have addressed plagiarism critically, not only as a means to improve academic ethics policies (PlagiarismAdvice.org, 2008), but mainly to demonstrate that if anything the concept of plagiarism is far from being universal (Howard & Robillard, 2008). Even if differently, Howard (1995) and Scollon (1994, 1995) argued, and Angèlil-Carter (2000) and Pecorari (2008) later emphasised that the concept of plagiarism cannot be studied on the grounds that one definition is clearly understandable by everyone. Scollon (1994, 1995), for example, claimed that authorship attribution is particularly a problem in non-native writing in English, and so did Pecorari (2008) in her comprehensive analysis of academic plagiarism. If among higher education students plagiarism is often a problem of literacy, with prior, conflicting social discourses that may interfere with academic discourse, as Angèlil-Carter (2000) demonstrates, we then have to aver that a distinction should be made between intentional and inadvertent plagiarism: plagiarism should be prosecuted when intentional, but if it is part of the learning process and results from the plagiarist’s unfamiliarity with the text or topic it should be considered ‘positive plagiarism’ (Howard, 1995: 796) and hence not an offense. Determining the intention behind the instances of plagiarism therefore determines the nature of the disciplinary action adopted. Unfortunately, in order to demonstrate the intention to deceive and charge students with accusations of plagiarism, teachers necessarily have to position themselves as ‘plagiarism police’, although it has been argued otherwise (Robillard, 2008). Practice demonstrates that in their daily activities teachers will find themselves being required a command of investigative skills and tools that they most often lack. We thus claim that the ‘intention to deceive’ cannot inevitably be dissociated from plagiarism as a legal issue, even if Garner (2009) asserts that generally plagiarism is immoral but not illegal, and Goldstein (2003) makes the same severance. However, these claims, and the claim that only cases of copyright infringement tend to go to court, have recently been challenged, mainly by forensic linguists, who have been actively involved in cases of plagiarism. Turell (2008), for instance, demonstrated that plagiarism is often connoted with an illegal appropriation of ideas. Previously, she (Turell, 2004) had demonstrated by comparison of four translations of Shakespeare’s Julius Caesar to Spanish that the use of linguistic evidence is able to demonstrate instances of plagiarism. This challenge is also reinforced by practice in international organisations, such as the IEEE, to whom plagiarism potentially has ‘severe ethical and legal consequences’ (IEEE, 2006: 57). What plagiarism definitions used by publishers and organisations have in common – and which the academia usually lacks – is their focus on the legal nature. We speculate that this is due to the relation they intentionally establish with copyright laws, whereas in education the focus tends to shift from the legal to the ethical aspects. However, the number of plagiarism cases taken to court is very small, and jurisprudence is still being developed on the topic. In countries within the Civil Law tradition, Turell (2008) claims, (forensic) linguists are seldom called upon as expert witnesses in cases of plagiarism, either because plagiarists are rarely taken to court or because there is little tradition of accepting linguistic evidence. In spite of the investigative and evidential potential of forensic linguistics to demonstrate the plagiarist’s intention or otherwise, this potential is restricted by the ability to identify a text as being suspect of plagiarism. In an era with such a massive textual production, ‘policing’ plagiarism thus becomes an extraordinarily difficult task without the assistance of plagiarism detection systems. Although plagiarism detection has attracted the attention of computer engineers and software developers for years, a lot of research is still needed. Given the investigative nature of academic plagiarism, plagiarism detection has of necessity to consider not only concepts of education and computational linguistics, but also forensic linguistics. Especially, if intended to counter claims of being a ‘simplistic response’ (Robillard & Howard, 2008). In this paper, we use a corpus of essays written by university students who were accused of plagiarism, to demonstrate that a forensic linguistic analysis of improper paraphrasing in suspect texts has the potential to identify and provide evidence of intention. A linguistic analysis of the corpus texts shows that the plagiarist acts on the paradigmatic axis to replace relevant lexical items with a related word from the same semantic field, i.e. a synonym, a subordinate, a superordinate, etc. In other words, relevant lexical items were replaced with related, but not identical, ones. Additionally, the analysis demonstrates that the word order is often changed intentionally to disguise the borrowing. On the other hand, the linguistic analysis of linking and explanatory verbs (i.e. referencing verbs) and prepositions shows that these have the potential to discriminate instances of ‘patchwriting’ and instances of plagiarism. This research demonstrates that the referencing verbs are borrowed from the original in an attempt to construct the new text cohesively when the plagiarism is inadvertent, and that the plagiarist has made an effort to prevent the reader from identifying the text as plagiarism, when it is intentional. In some of these cases, the referencing elements prove being able to identify direct quotations and thus ‘betray’ and denounce plagiarism. Finally, we demonstrate that a forensic linguistic analysis of these verbs is critical to allow detection software to identify them as proper paraphrasing and not – mistakenly and simplistically – as plagiarism.

An introduction to forensic linguistics:language in evidence

From the accusation of plagiarism in The Da Vinci Code, to the infamous hoaxer in the Yorkshire Ripper case, the use of linguistic evidence in court and the number of linguists called to act as expert witnesses in court trials has increased rapidly in the past fifteen years. An Introduction to Forensic Linguistics: Language in Evidence provides a timely and accessible introduction to this rapidly expanding subject. Using knowledge and experience gained in legal settings – Malcolm Coulthard in his work as an expert witness and Alison Johnson in her work as a West Midlands police officer – the two authors combine an array of perspectives into a distinctly unified textbook, focusing throughout on evidence from real and often high profile cases including serial killer Harold Shipman, the Bridgewater Four and the Birmingham Six. Divided into two sections, 'The Language of the Legal Process' and 'Language as Evidence', the book covers the key topics of the field. The first section looks at legal language, the structures of legal genres and the collection and testing of evidence from the initial police interview through to examination and cross-examination in the courtroom. The second section focuses on the role of the forensic linguist, the forensic phonetician and the document examiner, as well as examining in detail the linguistic investigation of authorship and plagiarism. With research tasks, suggested reading and website references provided at the end of each chapter, An Introduction to Forensic Linguistics: Language in Evidence is the essential textbook for courses in forensic linguistics and language of the law.

Forensic linguistics : the application of language description in legal contexts

In this article I first divide Forensic Linguistics into three sub-disciplines: the language of written legal texts, the spoken language of legal proceedings, and the linguist as expert witness and then go on to give a small number of examples of the research undertaken in these three areas. For the language of written legal texts, I present work on the (in) comprehensibility of police cautions and of judges instructions to juries. For the spoken language of legal proceedings, I report work on the problems of interpreted interaction, of vulnerable witnesses and the need for more detailed research comparing the interactive rules in adversarial and investigative systems. Finally, to illustrate the role of the linguist as expert witness I report a trademark case, five different authorship attribution cases, three very different plagiarism cases and I end reporting briefly the contribution of linguists to language assessment techniques used in the linguistic classification of asylum seekers. © Langage et société no 132 - juin 2010.