Friday, November 21, 2008

Computer science in the news

The New York Times magazine has a feature this week on the NetFlix challenge:

Its actually puts computer science in a pretty nice light -- it makes it seem very exciting. In particular, it seems to take the position that complex machine learning systems have something approaching real intelligence -- or at least that they are complex enough that they aren't fully understood by their own creators:

There’s a sort of unsettling, alien quality to their computers’ results. When the teams examine the ways that singular value decomposition is slotting movies into categories, sometimes it makes sense to them — as when the computer highlights what appears to be some essence of nerdiness in a bunch of sci-fi movies. But many categorizations are now so obscure that they cannot see the reasoning behind them. Possibly the algorithms are finding connections so deep and subconscious that customers themselves wouldn’t even recognize them. At one point, Chabbert showed me a list of movies that his algorithm had discovered share some ineffable similarity; it includes a historical movie, “Joan of Arc,” a wrestling video, “W.W.E.: SummerSlam 2004,” the comedy “It Had to Be You” and a version of Charles Dickens’s “Bleak House.”  For the life of me, I can’t figure out what possible connection they have, but Chabbert assures me that this singular value decomposition scored 4 percent higher than Cinematch — so it must be doing something right.

The author is definitely giving the computer too much credit for these anomylous clusters (and holds up "singular value decomposition" throughout the article as some sort of magical technique), but the point made is the right one. The difference between real intelligence and "just an algorithm" does in large part seem to be whether or not you can anticipate what its going to do. When you create a program that can come up with output that surprises you, thats pretty cool.

1 comment:

Arvind Narayanan said...

Well, when writing for a general audience you have to use some kind of hand waving to get across the point that the intelligence of the algorithms being used far exceeds our capacity to understand them. Whether it's SVD or something else doesn't make too much of a difference to the reader. I find it entirely forgivable.

BTW, see this article on the same topic that might even surprise most computer scientists. And in the light of the discussion there, I don't think he's giving the computer too much credit.