Question

I was wondering if such algorithm exists. I have a bunch of text documents and would like to find a pattern among all these documents, if a pattern exists. Please note im NOT trying to classify the documents all i want to do is find a pattern if it exists among some documents. Thanks!

Answer 1

The question as it stands now is kinda vague.. you kinda need to know what you are looking for in order to be able to find it.
Some ideas that may be of use –

1. Get n-gram counts for each document separately for n = 1,2,3,4 and then compare the frequencies of each ngram across the documents. This should help you find commonly occuring phrases across all documents.
2. Get a part of speech tagger to get convert all the docs into a stream of POS tags and then do the same as 1
3. Use a PCFG software such as the Stanford Parser to get parse trees for all the sentences across all the documents, and then try to figure out how similar the distribution of sentence structures are for different documents.