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Using Full Text Databases to Detect Plagiarism

Below are examples from two databases of how you can use a full text library database to detect plagiarism:

• PsycARTICLES
• Research Library

These are merely two of the resources from which students may have plagiarized. We suggest reading through both of the examples below, even if they are not related to your subject area, to get a flavor of how to search library databases in order to verify plagiarism.

PsycARTICLES

Suppose that you encounter the following in a student paper and wonder whether it was plagiarized.

The story model for juror decision-making (Pennington & Hastie, 1986) is the most influential approach of this type and proposes that jurors formulate a plausible story of the crime, and subsequently, arrive at a verdict consistent with that particular story. Thus, story construction constitutes a central feature of the cognitive process implemented by jurors to handle trial information in a courtroom setting. As pretrial publicity typically exerts a cognitive impact in advance of the trial and testimony evaluation, an examination of the process by which the publicity information feeds into the decision-making process is necessary. For instance, it may be the case that PTP works to make one “story” more credible than other competing explanations of the crime event or, as is examined in the current article, it may be the case that exposure to PTP promotes a proprosecution bias that determines the subsequent evaluation of each piece of evidence to produce a particular final proprosecution story.

One database you may wish to check is Psycarticles. This database appears in the library's list of databases. Select a phrase from the above paragraph to search in the database.  An example could be "pretrial publicity typically exerts a cognitive impact in advance". (Phrase searching is not the only method to try, as we mention later in the document.) Try different phrases, since a student may have taken certain phrases with alteration but in other cases altered them. Trying a number of examples can increase the chances that you will be able to verify plagiarism.

To see how to do phrase searches in this database, check the help documentation. You'll find that to do phrase searching, enclose the search string in quotes.

The screen shot below illustrates how to enter the phrase : " pretrial publicity typically exerts a cognitive impact in advance".

The following result comes up:

Click on the HTML version of the article and use the find feature to see whether the text appears in the article. Drag down the edit menu and select "find in this page", and type in a phrase (for example, type in cognitive impact) from the plagiarized item:

Click on "Find"; this will bring you to the following, which confirms that the students indeed plagiarized from this article:

Above we showed how to search the phrase : " pretrial publicity typically exerts a cognitive impact in advance".

Keep in mind that phrase searching is not the only method to check. A student may have taken a phrase from the original source and rearranged elements within it. For example, the student may take the phrase above and rearrange it to read: an advance cognitive impact can be exerted by pretrial publicity

You can do a keyword search by selecting some words from the original phrase, such as pretrial and cognitive and publicity, and run a search on these as follows:

This produces --unsurprisingly -- 8 search results, since we are now not picking out an exact phrase but a variety of keywords that can appear in various articles.. Experiment with different keywords.

Research Library

Here is another example of a student paper that might seem to have been plagiarized:

Mill had no occasion to think about statistical differences when he was writing in 1843.  Statistical differences were only just beginning to loom large on the scientific horizon. New concepts are needed-- 'significant,' 'meaningful,' and 'useful.' All three go with the dread word 'statistical.'   When discussing so-called races, namely, geographically and historically identified groups of people, we are talking about populations. And we are talking about some characteristic or property of some but not all members of a population.

This time we try a search on Research library, which appears in the library's list of databases. Follow these steps:

1. Select   Search
2. Change the default search from “citation and abstract” to “citation and document text” using the pull down on the right
3. Limit search to full-text documents only
4. Paste the up to 145 characters of text into the 1st search box—delete any punctuation
5. Paste a distinctive name or word into the 2nd search box

 In this example, by combining distinctive phrases ("occasion to think about statistical differences" or "loom large on the scientific horizon or geographically [CHECK WITH JEAN--SHOULD BE "OR"?]   and historically identified groups of people") and a distinctive name, Mill, one gets a hit, the article from Daedalus by Ian Hacking. 

The search produces Ian Hacking’s 2005 article, Why race still matters.  Daedalus 134, no. 1 (January 1): 102-116.  http://www.proquest.com/ (accessed November 22, 2005). In the article, we find this passage.

Writing in 1843, Mill had little occasion to think about statistical differences, which were only just beginning to loom large on the scientific horizon. We need some new concepts: I will use the words 'significant,' 'meaningful,' and 'useful.' All three go with the dread word 'statistical.' Since we are among other things talking about so-called races, namely, geographically and historically identified groups of people, we are talking about populations. And we are talking about some characteristic or property of some but not all members of a population.

 Now compare the two passages; color coding indicates plagiarized content:

Student's paper:

Mill had no occasion to think about statistical differences when he was writing in 1843.  Statistical differences were only just beginning to loom large on the scientific horizon. New concepts are needed-- 'significant,' 'meaningful,' and 'useful.' All three go with the dread word 'statistical.'   When discussing so-called races, namely, geographically and historically identified groups of people, we are talking about populations. And we are talking about some characteristic or property of some but not all members of a population.

Article from Research Library:

Writing in 1843, Mill had little occasion to think about statistical differences, which were only just beginning to loom large on the scientific horizon. We need some new concepts: I will use the words 'significant,' 'meaningful,' and 'useful.' All three go with the dread word 'statistical.' Since we are among other things talking about so-called races, namely, geographically and historically identified groups of people, we are talking about populations. And we are talking about some characteristic or property of some but not all members of a population.

As indicated in the example from PsycARTICLES above, you may want to try a keyword search as well. This can be useful if the student "scrambled" various words that appear within phrases, such that a phrase search would not be the best way to locate the item.

Here is help documentation about using "AND" to search for keywords:

For example, here is a keyword search over three terms that appear in the student's work:

This results in the following search result, which happens in this case to be identical (though need not have been) to the one discovered above.