A new study of student plagiarism finds that the vast majority of “unoriginal” content in papers comes from legitimate sites rather than paper mills and “cheat” sites.

Turnitin, billed as the “leading academic plagiarism detector,” examined nearly 40 million student papers and 140 million “content matches” — instances where passages in papers matched something in an archived Web page.

Today’s students are a bit fuzzy on the difference between original and copied work. Pasting something from Wikipedia into a paper without proper citation is plagiarism. Yet many students apparently are so accustomed to sharing online text that they simply miss this distinction.

Think about it: Today’s student can assemble a 10-page paper on any topic in a few minutes simply by doing a Google search and copying blocks of text from here and there. In the old days, such wholesale theft at least required the writer to physically copy the text, a time-consuming task.

Here’s what the study found:

One-third of all unoriginal content in student papers came from social networks, including Facebook and all of the various “content-sharing” sites where users post and share information, such as Answers.com. It’s an interesting finding, because typically, the content of those sites is unverified and unsourced. Users may say pretty much whatever they want, factual or not.

One-fourth of copied content came from educational Web sites, including homework-help sites and organizational Web sites for nonprofits and government agencies and the like. Much of that content is presumably factual, although clearly not all.

Fourteen percent of content was copied from news Web sites, including this one. Factual? Hey, we try.

Ten percent came from encyclopedias. One of them, Wikipedia, is the single most popular Web site for student scholars.

Fifteen percent of unoriginal content came from Web sites that are “geared toward cheating and academic dishonesty,” the paper states. Such sites, including www.oppapers.com and www.allfreepapers.com, “seek to profit from student need by either selling, exchanging or placing advertising around offers of original student papers.”

One important note: The study did not consider whether students properly cited the copied material. So one cannot draw a conclusion from this study that only 15 percent of plagiarized content comes from cheat sites. It may be that the large majority of content copied from Wikipedia, for example, is properly cited. On the other hand, it’s hard to imagine that student writers would cite material lifted from a cheat site.

The study urges educators to teach proper citation to students who have grown up in a copy-and-paste world.

I close with a list of the eight most popular sites for unoriginal content in student papers.

1. Wikipedia

2. Yahoo! Answers

3. Answers.com

4. Slideshare

5. OPPapers

6. Scribd

7. Coursehero

8. Medlibrary

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