Monday, February 23, 2009

Bash

Posted by Danny Tarlow
This page addresses every complaint I had about the way the bash shell handles my command history. I made every recommended change: http://www.geocities.com/h2428/petar/bash_hist.htm

Thursday, February 12, 2009

Birthdays

Posted by Danny Tarlow
In honor of my 25th birthday, I would like to give some attention to my eight-times-older birthday mates, Abraham Lincoln and Charles Darwin. Darwin: Lincoln: I'll be celebrating my milestone by trying to polish of a conference submission on using machine learning to better predict how we use energy in buildings.

Wednesday, February 11, 2009

Monday, February 9, 2009

Google overflow

Posted by Danny Tarlow
Jeff Atwood shows some numbers on where his traffic comes from for the site that he works on, StackOverflow.com. The organic traffic numbers from Google compared to the other search engines are pretty incredible:
Search EngineVisits
Google3,417,919
Yahoo9,779
Live5,638
Search2,961
AOL1,274
Ask1,186
MSN1,177
Altavista202
Yandex191
Seznam103
One take-away point here might be that whatever they're doing for search engine optimization purposes is working. More at his post: http://www.codinghorror.com/blog/archives/001224.html

How bad is it?

Posted by Danny Tarlow
Justin Fox reproduced Nancy Pelosi's graph of how bad the job losses are in this economy compared to past recessions, but he added data for several more than just the most recent two. I think this is a more compelling chart than the original Pelosi one. It says that things are as bad as they've been, but we're not (yet) in worse territory than we hit in the worst of the 70s and worst of the 80s. Pelosi's original only had the beige, purple and light blue lines. There's also an interesting follow up from fivethirtyeight.com. If you look at the duration of the recessions, there is a trend where they are getting longer--you can see this in the strong correlation between how recent the recession was and where the lines return back up to the x-axis.

Sunday, February 8, 2009

Facelift

Posted by Danny Tarlow
I redid the color and layout of this blog to better match the color scheme at my University of Toronto research page. I doubt Google is sophisticated enough to appreciate matching color schemes, but hopefully my non-robot readers will.

Friday, February 6, 2009

AISTATS art expo

Posted by Danny Tarlow
This oughta be interesting. The idea is to come up with an algorithm that takes an image as input and produces an artistic looking image as output. The rules seem to be very lax--nothing I can see rules out an algorithm that ignores the input and just produces a neat looking image. Presumably the judges will be looking for something more creative than that, though. http://www.ics.uci.edu/~aistats/artexpo.htm

Thursday, February 5, 2009

Next generation math education

Posted by Danny Tarlow
We all know mathematicians can be a kooky bunch, but what is this world coming to? http://www.amazon.com/Concrete-Contemporary-Abstract-Introduction-Solution/dp/1441451579/
To imagine a taste of the book take a glance at the formulation of one theorem: "Every fuckin' shitty non-constant single-variable unfucked polynomial with fucky complex coefficients has at least one fucked complex root." Get ready to be completely shocked!

Riemann

Posted by Danny Tarlow
Some (non-mathematician) friends and I had an email discussion going on tangentially related to the Riemann hypothesis a while back, in the context of what you can say about infinite products over p in prime numbers of 1 / (1 - p^2). Strangely enough, it is equal to the Riemann zeta function (in the specific case where s = 2): http://en.wikipedia.org/wiki/Proof_of_the_Euler_product_formula_for_the_Riemann_zeta_function It's pretty interesting stuff. Using the connection to the Riemann zeta function, you can show that our infinite product converges to pi^2 / 6. It's pretty amazing to me that there is this relationship between pi and the prime numbers: http://en.wikipedia.org/wiki/Basel_problem But anyway, there is a (possible) development on the Riemann hypothesis front. John Cook says it better than I would: http://www.johndcook.com/blog/2009/02/05/proposed-riemann-hypothesis-proof-by-julio-alcantara-bode/ Aside from satiating our interest, I'm still not clear on whether there would be any practical implications of proving the Riemann hypothesis. At least from my limited understanding of the problem, it sounds like most people are pretty convinced that it's true, based on lots of empirical evaluation. We just don't have a formal argument of why. Update: Thanks, Carlos.
Abstract: This paper has been withdrawn by the author, due to a crucial error in page 5.
(http://arxiv.org/abs/0902.0617)