22 September 2009

The Nobel, the Fields, and the .... Netflix?



Well, of course, there is no Nobel prize in mathematics. The prestigious Fields Medal is similar (although only awarded every 4 years and only those younger than 40). Notably, some prizes in mathematics and related disciplines, such as the famous  Millennium Prize Problems, are awarded only for providing a solution to specific problems. In the case of the Millenium Prize, only one prize has been awarded, for the PoincarĂ© conjecture theorem. Others, including P vs NP, are still up in the air.

This is all pretty dry stuff, although important. The Poincare conjecture is about the topology of 3-spheres; the other Fields Medals last awarded involved topics such as Schramm-Loewner evolution; and P vs NP is a computability conjecture. It's all interesting, sometimes even exciting to math geeks like me -- it's just not of general interest or immediate utility. Unlike the Netflix prize.

Netflix? Yeah, them. The Netflix prize is a US$1,000,000 prize for better recommendations algorithms. It's easy to recognize the general interest and utility here. Consumers get movies they like. DVD publishers get more business. Netflix gets happier customers. But what about the math? It's real math, and an important area of research. Just check out all the papers from the Association for Computing Machinery (ACM) web site:  [Google search].  Real mathematical research that's useful and cool.

The Netflix prize was recently awarded to a team of researchers called BellKore's Pragmatic Chaos. Their paper can be found here [PDF]. They used Restricted Boltzmann Machines (RBMs). An RBM is a kind of neural network which is able to learn how to solve combinatorial problems -- the science of connections and criteria.

The result means not only a better algorithm for Netflix, but also great research being done in this area, which advances the general state of science and provides useful technology for improving our life experiences.  Netflix is not sitting still; they have extended the contest to Netflix Prize 2 (The Sequel).

This is a great trend, this meeting of mathematical research with entrepreneurialism. I hope this trend picks up lots of momentum.  In my opinion, this is also the way that is most likely to renew the future of space science...combine research and entrepreneurialism.

Citius, altius, fortius!