Linkage

The Voice of the T announcements (h/t Erin). Features a special guest appearance by not-me.

Videos from the 2010 Kailath Lecture and Colloquium have been posted (h/t Pulkit Grover).

The Supreme Court issued a 4-4 per curiam decision affirming (pdf) the Ninth Circuit Court’s decision in Costco vs. Omega. Basically Omega sells its watches cheaper abroad, and Costco was re-importing them from a reseller to give the discount to US customers. This was a copyright violation, says Omega, and the Ninth Circuit reverse the lower court decision in favor of Costco. Why does this matter? As I mentioned earlier, a decision for Costco would let resellers sell cheap textbooks in the US. When I was in Delhi I picked up a copy of Feller Vol. 1 (the Vol. 2 was a little beat up so I decided to get it another time) for Rs. 400 (under 10 bucks), a savings of over $120 from the price on Amazon. Admittedly, it’s softcover and the paper is not quite as nice, but the way publishers gouge people on technical books is astonishing.

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Wiener on control versus learning

I’ve seen this quote excerpted in parts before, but not the whole thing:

I repeat, feedback is a method for controlling a system by reinserting into it the results of its past performance. If these results are merely used as numerical data for the criticism of the system and its regulation, we have the simple feedback of the control engineers. If, however, the information which proceeds backward from the performance is able to change the general method and pattern of performance, we have a process which may well be called learning.
– Norbert Wiener, The Human Use of Human Beings

It is a strange distinction Wiener is trying to make here. First, Wiener tries to make “numerical data” a simple special case, and equates control as the manipulation of numerical data. However, he doesn’t contrast numbers with something else (presumably non-numerical) which can “change the general method and pattern.” Taking it from the other direction, he implies that mere control engineering cannot accomplish “learning.” That is, from numerical data and “criticism of the system” we cannot change how the system works. By Wiener’s lights, pretty much all of the work in mathematical control and machine learning would be classified as control.

I am, of course, missing the context in which Wiener was writing. But I’m not sure what I’m missing. For example, at the time a “control engineer” may have been more of a regulator, so in the first case Wiener may be referring to putting a human in the loop. In the book he makes a distinction between data and algorithms (the “taping”) which has been fuzzed up by computer science. If this distinction leads to drawing a line between control and learning, then is there a distinction between control and learning?