Weka is a collection of machine learning algorithms for data mining tasks. The algorithms can either be applied directly to a dataset or called from your own Java code. Weka contains tools for data pre-processing, classification, regression, clustering, association rules, and visualization. It is also well-suited for developing new machine learning schemes. Weka is open source software issued under the GNU General Public License.

find details and downloads here:
http://www.cs.waikato.ac.nz/ml/weka/

相关书籍：
Ian H. Witten, Eibe Frank《Data Mining: Practical Machine Learning Tools and Techniques with Java Implementations》

开始用的时候对java还不熟悉，拿来学java还是挺爽的。

建议找个j2se安装上，再装虚拟机，然后再安装weka。

其实我觉得用netbeans-3_6-windows-zh可能效果更好一些，这个可以从sun公司的站点里面下载。

http://www.eti.hku.hk/alphaminer/

下载开源 数据挖掘软件 AlphaMiner！

我试用了一段时间，很好用。GUI 很相似WEKA。