D.R. Jones Judy Kaul Case Western Reserve University School of Law Library Plagiarism Detection Software2

D.R. Jones

Judy Kaul

Case Western Reserve University School of Law Library

Plagiarism Detection Software2

CALI 2004: Plagiarism Detection Software

PDS

Bibliography lists articles that evaluate various systems

Some no longer in existence Beware of My Drop Box, aka Plagiserve,

EduTie.com: Suspected of uploading student papers to term paper mills


Detection with Software or Systems

Natural language (text) programs Turnitin (Plagiarism.org)

http://www.plagiarism.org http://www.turnitin.com

Essay Verification Engine (EVE2) http://www.canexus.com/eve/


Detection with Software

Glatt CD-ROM Tests students knowledge of “own” work

WCopyFind: Used with Google or other search engines

Alternative tool: LexisNexis CiteCheck


Turnitin: What It Does

Searches 8-word strings Currently searches against 3 databases of content:

Currently & extensively archived copy of publicly accessible Internet pages & term paper mills (2 billion)

ABI/Inform, Periodical Abstracts, Business Dateline (ProQuest)

“Tens of thousands of electronic books” Every student paper ever submitted to Turnitin Does seem to retrieve PDFs


Turnitin: What It Does

iThenticate© algorithm: able to detect embedded paragraphs from multiple sources


Turnitin: Reports

Yields Two Reports Printable report: 2 sections Originality Report: 3 sections Percentage of Suspected Plagiarism Color

Coded


Turnitin: Limitations

Once submitted, a paper is only reported as a paper in the database- no originality report—even if serious evidence exists

Reports first several relevant hits—but they may not be the actual official original source

Presently does not search LexisNexis, Westlaw & Hein-Online


Turnitin: Value to Law Schools

Value for Law Schools could be improved if it could also search LexisNexis, Westlaw and Hein-Online


EVE2: What It Does

User identifies file from local system EVE2 strips formatting –turns into plain text Uses “Advanced Searching Tools” to match

potential sources from the internet Does search term paper mills Not much more information forthcoming

from EVE


EVE2: Limitations

Seems to ignore punctuation, e.g., quotation marks, resulting in false hits

Varying results If you run 3 times in a row, you can get different

percentage of suspected plagiarism


EVE2: Advantages

Low-cost if you just have a one-time paper you need to check Even Turnitin will recommend this product

Generates report in RTF and saves automatically to your hard drive


Turnitin Pricing

Site license: Plagiarism Prevention Single campus institution (12 months) $500.00 annual licensing fee + .60 per

student (Minimum: $1100.00) Unlimited classes/instructors Unlimited originality reports Campus administrator with department

administrator options


Turnitin Pricing - Extras

Additional costs for: Extended HelpDesk for Faculty (E-mail only)

would be 20% total cost: $220 Extended HelpDesk for Faculty & Students (E-

mail only) = 30% total cost: $330


EVE2

Time consuming search runs from your computer Searches the internet, including term paper mills Yields 2 part report:

List of sources Highlighted student paper Click on comparison option to see side-by-side Also time consuming


WCopyFind

http://plagiarism.phys.virginia.edu/Wsoftware.html Developed at University of Virginia Simple program Generates report comparing the student paper and

documents you locate with Google. Shareware Limitation: Finding sources for comparison Limitation: Doesn’t search internet or databases


LexisNexis CheckCite

Not a PDS You can get clues that quotation marks are

missing Only works with cases and law review

articles Only generates sample report for case law?


Demos

http://www.turnitin.com/ Eve2 http://www.canexus.com/eve/ WCopyFind http://plagiarism.phys.virginia.edu/Wsoftware.html


Plagiarism Detection Strategies

Most complete list in Paul Clough’s article:

“Plagiarism in Natural and Programming Languages: An Overview of Current Tools and Technologies” (2000)

http://www.dcs.shef.ac.uk/~clough/papers/Plagiarism.pdf


Clough’s Detection Strategies

Uses of vocabulary Changes in vocabulary Dependence on unique words & phrases Frequency of words Distribution of words Common spelling mistakes


Clough’s List

Statistical similarities Readability of text

Flesch Reading Ease Formula SMOG Index

Average length of sentences (words) Average length of paragraphs (sentences) Usage of passive voice (expressed as percentage) Number of prepositions as % of total number of words

CALI 2004: Plagiarism Detection SoftwareClough’s Detection Strategies

(continued)

Long sequences common text – unattributed

Order of presentation of information, facts Amount of similarity of text Sudden incoherence of text Preference for long or short sentences


More signals

Abrupt stylistic changes Format variations Footnotes don’t jive with text Different citation formats Change of level of sophistication

Documents

D.R. Jones Judy Kaul Case Western Reserve University School of Law Library Plagiarism Detection Software2