Sunday, November 30, 2008


ShowMeDo contains a large collection of short video tutorials for Python programming and a lot more.


Thompson/Reuters provides a free web-service OpenCalais that can be used for information extraction from unstructured text/html/xml documents. It can recognize not only named entities, but also facts and events. There is a Python interface available to this Web service called python-calais.

Friday, November 21, 2008

Efficient SVM for Ranking

Ranking Vector Machine improves the efficiency of the standard Ranking SVM (as implemented in SVM-light) by (1) using L_1 norm instead of L_2 norm for regularisation; and (2) using a subset of the original instance vectors rather than the pairwise difference vectors as support vectors. It is said to be much faster than Ranking SVM if non-linear kernels are employed, though with a lower accuracy (especially on small datasets).