SAGE

I really believe that Python, but not Matlab, is the future for scientific and engineering computing. SAGE, a free open-source alternative to Matlab etc., has started to attract attention from the research community. Since it uses Python instead of an obscure language designed for a particular mathematics program, one can write programs that combine serious mathematics with anything else, such as natual language processing.

Right Data vs. Better Models

Yehuda Koren, a member of the famous BellKor team in the Netflix Prize competition, recently wrote an article about the three levels of addressing the Netflix Prize. The insight that deciding what data to model is more important than choosing what model to use seems to be complement to the issue of more data vs. better algorithms. This is also supported by the successful story of Amazon's recommendation systems.

Generating all permutations: a non-recursive algorithm

A natural idea for generating all permutations of n elements is to write a recursive algorithm with O(n!) time complexity. The algorithm used in C++ STL function next_permutation is a more efficient solution --- it generates all unique permutations non-recursively and moreover in lexicographic order. The algorithm is given by the great computer scientist Donald Knuth in his book The Art of Computer Programming, Volume 4, Fascicle 2: Generating All Tuples and Permutations. Here is his Draft of Section 7.2.1.2: Generating All Permutations.

ParsCit

ParsCit is an open-source reference string parsing package developed by Min-Yen Kan et al. It is based on the Conditional Random Fields (CRF) toolkit CRF++. It is being used by the well-known computer science digital library CiteSeer^x.

More Data vs. Better Algorithms

The recent blog posts from Anand Rajaraman that more data usually beats better algorithms (part 1, part 2 and part 3) reminds me of a talk by David Hand two years ago --- Classifier Technology and the Illusion of Progress. There has also been discussons on a this issue in Hal Daume III's blog post about Heuristics.