Notes on Yoav Freund and Robert E. Schapire, Game Theory, On-line Prediction, and Boosting

This is a set of notes for a paper covered by the learning theory reading group, which I’m posting here with some keywords so I can easily search for them. I doubt they’ll be useful for anyone else, but who knows?

These notes cover the whole paper. Despite the usual disclaimer, this set of notes may actually be thorough enough to be useful to someone besides myself because I was presenting this week. The exposition in the paper is excellent, and it’s pretty basic, so you’re probably still better off just reading the paper directly, though :-).

Continue reading “Notes on Yoav Freund and Robert E. Schapire, Game Theory, On-line Prediction, and Boosting”

Notes on Yoav Freund and Robert E. Schapire, Game Theory, On-line Prediction, and Boosting

How does the Austin Public Library come up with its fee schedule?

I spilled some soy sauce on a book, staining the edge of a few pages. Considering the condition I’ve seen some APL books in, I doubt the damage would have been noticed had I not pointed out the damage and volunteered to pay whatever fine they wanted to impose. Today, on attempting to renew a book, I find that my account is blocked because I have a $26.50 fine. That would be a bit surprising for any book, since it’s just a few drops of soy sauce, but it seems especially strange in this case because the book retails for $15 and the exact edition I damaged is available new on amazon for $10 (and used for $.01). Does it really cost them $16.50 to stock a new book?

I’m not complaining: considering how much benefit I get from the library and how much I donate, I’m still getting a great deal; I view this as an additional (well deserved) donation to the library. Just sayin’, this fee structure strikes me as being a bit unusual.

How does the Austin Public Library come up with its fee schedule?

The Deadwight Loss of Thanksgiving Dinner Potlucks

I’m not one of these people who complains about the deadweight loss of Christmas. If you want to get all homo economicus, presents are a valuable signal: finding out how well someone really knows you is hard (expensive), whereas buying a book or even a TV is easy (cheap). Potlucks, on the other hand, bug me to no end.

Cooking has obvious economies of scale: cooking ten times as much of a dish takes perhaps twice as long; and cooking ten times as many dishes has about the same overhead, because so much can be done in parallel (and the relative overhead is even lower, if you consider cleanup time). Having each person prepare a single dish is the most inefficient possible way to go about it. Furthermore, not everyone has the same aptitude for cooking: division of labor, people! Worse yet, each person inevitably brings at least one dish or dessert that’s large enough to feed five or ten people (and oftentimes more than one), so there’s an order of magnitude food than necessary, much of which goes to waste (leftovers aren’t as good as freshly made food, so this is lossy even if the food gets eaten).

P.S. If you’re in Austin, and want some leftover pie (apple, pecan, or pumpkin), cake (chocolate), side dishes (green bean casserole, stuffing, or gravy), meat (turkey or chicken), or meat substitute (seitan or tofu) let me know.

The Deadwight Loss of Thanksgiving Dinner Potlucks

Pervasive Computing + Architecure = ?

There was an interesting side discussion about the level of control over things like lighting that you might want in an “intelligent environment” at Seth’s proposal.

That was already off topic, and I didn’t want to derail the conversation even further, but it reminded me of the chapter in the original design patterns book* where Chris points out that it’s good to have windows on three sides of a room to avoid harsh contrasts between light and dark. That’s one way to do it, but it’s hard (and expensive) to design a building to meet that constraint, if you want to have natural light in every room; it wouldn’t be hard to have embedded sensors and adjustable lighting fix the problem, though.

What other architectural design patterns can be worked around with a bit of cheap technology? I see a lot of modernist architecture that takes advantage of advances in materials science to create interesting looking structures that would have been impossible centuries ago, and I see some of what I think of as Jane Jacobs style patterns, where classical ideas are used to create comfortable spaces that people actually want to use, but I don’t see much use of cutting edge technology to create really livable space. Why is that, and what can we do about it?

*Christopher Alexendar’s A Pattern Language, not the GoF Design Patterns book :-)

Pervasive Computing + Architecure = ?

Notes on NH Bshouty, E Mossel, R O’Donnel, and RA Servedio: Learning DNF from Random Walks

This is a set of notes for a paper from the learning theory reading group, which I’m posting here with some keywords so I can easily search for them. I doubt they’ll be useful for anyone else, but who knows?

Continue reading “Notes on NH Bshouty, E Mossel, R O’Donnel, and RA Servedio: Learning DNF from Random Walks”

Notes on NH Bshouty, E Mossel, R O’Donnel, and RA Servedio: Learning DNF from Random Walks

Running Programming Clojure Examples on Clojure Box

Stuart Halloway’s Programming Clojure book is the only game in town for learning Clojure (at least until Luke VanderHart’s Practical Clojure is released), and Clojure Box is the easiest way to get Clojure running on Windows with a good IDE, if you don’t already have cygwin installed, but they don’t quite play nicely out of the box.

Craig McDaniel has some generally useful code for Emacs/Clojure, and that’s almost enough to get things working. With the following changes incorporated, all of the examples work for me:

(defun reset-swank ()
  "Because changing swank-clojure-extra-classpaths is not enough to force a new instance of slime to use it."
  (interactive)
  (setq slime-lisp-implementations
        (assq-delete-all 'clojure slime-lisp-implementations))
  (add-to-list 'slime-lisp-implementations
               `(clojure ,(swank-clojure-cmd) :init swank-clojure-init) t))
 
(defun run-slime (dir)
  (interactive "Project directory: ")
  (cd dir)
  (when (file-directory-p "~/.clojure") (directory-files "~/.clojure" t ".jar$")) 
    (make-directory "classes"))
  (setq swank-clojure-extra-classpaths '("src" "classes" "lib/*" ""))
  (reset-swank)
  (slime))
Running Programming Clojure Examples on Clojure Box