To get a handle on the algorithms and the basics behind each of the algorithms, be they for clustering, classification or attribute selection, etc, I suggest  take up a good text book which will help understand the fundamentals. There are lots of great books available, which will present a clear and consice picture of the data mining tools, artificial intelligence methodologies or the machine learning methods, some of which are implemented in Weka. Here find listed some of the books you could use for gaining deeper insights:
1. To start with, Whitten & Frank's book on Data Mining is a great one. This is the book Weka refers to. There are also ones by Han; D. Hand on the same topic and widely used.
2. For Artificial Intelligence, Russel and Norvig; or Winston; or Knight or Charniak are widely read authors.
In addition to all the books, there are a host of materials available on the internet inthe form of tutorials slides, papers, articles and even open source training material that can be very useful and also handy. MIT has a great open source tutorial, most good Universities have some teaching material posted by professors which you can read.
Hope this should help,

From: wekalist-bounces@list.scms.waikato.ac.nz [mailto:wekalist-bounces@list.scms.waikato.ac.nz] On Behalf Of Andhra Loyola College
Sent: Thursday, February 07, 2008 12:13 PM
To: wekalist@list.scms.waikato.ac.nz
Subject: [Wekalist] where can i find algorithms explanation

dear weka forum,
                         I had gone through all the documentations present in source forge, but i could not find clear explanation of the algorithms.Can some one tell me where i can find them in Internet.
thank u.

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