statistical similarity of two text
Hello, Does anybody know where I can find program on the website which compare two text/article and settle whether or not they are similar assuming any significant level. Thanks in advance Cantor = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: statistical similarity of two text
On Tue, 17 Jul 2001, Cantor wrote: > Does anybody know where I can find program on the website which [can] > compare two texts/articles and settle whether or not they are similar > assuming any significant level. Sorry, Cantor: this is not possible, in general. One can discover whether two (or more) things _differ_ (on some quantitative measure) at a specified significance level (when this is a reasonable thing to do -- it isn't always reasonable), but the formal definition of "significant" in statistical analysis does not permit discovering whether two (or more) things are _similar_. However, it may suffice for your purposes to discover that two things are not different enough that you can tell them apart (which is not the same thing as discovering that they are the same), on whatever measure (or set of measures) you choose to analyze. Whether this be a useful outcome or not depends heavily on how much information you have (that is, on the size of the sample available) on the things being compared. In any case, the hard part is defining the characteristics, or properties, or measures, on which the two texts/articles are to be compared. Donald F. Burrill [EMAIL PROTECTED] 184 Nashua Road, Bedford, NH 03110 603-471-7128 = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: statistical similarity of two text
On 18 Jul 2001 03:41:57 -0700, [EMAIL PROTECTED] (Donald Burrill) wrote: > On Tue, 17 Jul 2001, Cantor wrote: > > > Does anybody know where I can find program on the website which [can] > > compare two texts/articles and settle whether or not they are similar > > assuming any significant level. DB > > Sorry, Cantor: this is not possible, in general. > One can discover whether two (or more) things _differ_ (on some > quantitative measure) at a specified significance level (when this is a > reasonable thing to do -- it isn't always reasonable), but the formal > definition of "significant" in statistical analysis does not permit > discovering whether two (or more) things are _similar_. > However, it may suffice for your purposes to discover that two things > are not different enough that you can tell them apart (which is not the > same thing as discovering that they are the same), on whatever measure Don, - this puts me in mind of other Similarities. We do not speak of "significance" but there are other things to describe, and "probability" comes into the descriptions Do we have a taxonomy of models? You just mentioned two or three questions: (a) two things are different; (b) two things are 'not different enough to tell apart'; (c) two things are shown to be the same. We have discussed "Bioequivalence" before - (b) and (c) are not EXACTLY the same problem, I don't think. Texts: Are two texts similar enough to be the same author? - to be assuredly the same author? ["Shakespeare?"][ Or, how many authors were there, of the books of the New Testament.] - to be plagiarism, or cheating on a test? Are these the same question, except that one concerns content and the other is style? Where similarity is accepted in court: P-levels have not been a concern with Fingerprints, but that is because those experts have done a peculiar job, insisting on HIGH confidence; and refusing to refuse to testify to the "partial" matches on degraded prints. DNA matching: probabilities have been more explicit. The lab work for blood-typing is similar, but the explicit probabilities are sometimes mediocre instead of convincingly extreme. My apologies for rambling. I didn't have a question to focus on, but maybe this will remind someone of something more that ought to be said about 'similarities' . -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: statistical similarity of two text
At 04:21 PM 7/19/01 -0400, Rich Ulrich wrote: >On 18 Jul 2001 03:41:57 -0700, [EMAIL PROTECTED] (Donald Burrill) >wrote: > > > On Tue, 17 Jul 2001, Cantor wrote: > > > > > Does anybody know where I can find program on the website which [can] > > > compare two texts/articles and settle whether or not they are similar > > > assuming any significant level. >DB > > > Sorry, Cantor: this is not possible, in general. some try however ... see http://www.turnitin.com ... a plagiarism detection company _ dennis roberts, educational psychology, penn state university 208 cedar, AC 8148632401, mailto:[EMAIL PROTECTED] http://roberts.ed.psu.edu/users/droberts/drober~1.htm = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: statistical similarity of two text
As Rich Ulrich and others have already said: Do you want to check "surface" similarity? You can use a bag-of-words representation and a cosine distance between two texts, or more sophisticated versions: See: An Information-Theoretic Definition of Similarity , by Dekang Lin: http://www.cs.ualberta.ca/~lindek/papers.htm Other people use clustering to find similarity: http://lsi.research.telcordia.com/lsi/LSIpapers.html I guess variants of these methods can be used to detect plagiarism. If you want to go deeper, to determine whether two text documents are about a similar subject - This is a much harder problem -- Yuval Feinstein email : [EMAIL PROTECTED] -- = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: statistical similarity of two text
"Cantor" <[EMAIL PROTECTED]> writes: >Does anybody know where I can find program on the website which compare two >text/article and settle whether or not they are similar assuming any >significant level. You may want to try Latent Semantic Analysis -- this technique looks at the meaning of the words used in the texts. It has been used to evaluate essays for the quality level of the writing. lsa.colorado.edu -- the site is down now but they did have a compare two texts web page. -Jason -- J. [EMAIL PROTECTED] Graduate Motto: Free-time with guilt. http://www.cs.ubc.ca/~harrison http://www.cs.ubc.ca/~harrison/dance = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =
Re: statistical similarity of two text
Similar on which aspects? Syntax? grammar? vocabulary? content? style?. I wrote a content analysis module called WordStat that can allows you to find the differences between two or more text (different authors, subgroups of individuals such as male vs female or age subgroups, etc.). You can analyze differences in word usage or in categories of words (predefined or user defined). You can download a trial version of WordStat from the following URL: www.simstat.com/wordstat.htm However, it won't necessarily provide you with a single p value and you will have to identify the dimension you want to compare, and if needed, create a categorization dictionary. You can also find a list of other computer-assisted text analysis (CATA) software from the following URL: www.intext.de/TEXTANAE.HTM Normand Peladeau Provalis Research "Cantor" <[EMAIL PROTECTED]> wrote in message news:9j1ir6$jbv$[EMAIL PROTECTED]... > Hello, > Does anybody know where I can find program on the website which compare two > text/article and settle whether or not they are similar assuming any > significant level. > > Thanks in advance > Cantor > > = Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =