30 November 2014 @ 06:20 pm
15 November 2014 @ 10:03 pm
15 October 2014 @ 01:30 pm
15 September 2014 @ 11:20 pm
31 August 2014 @ 10:59 pm
More Google+ links from the last couple of weeks:

The nymwars are the struggle to maintain online safe havens for pseudonymous free speech, for people who don't feel safe linking their opinions with their real names (for fear of religious persecution / sexual predation / current or future job prospects / whatever else) in the face of attempts by Facebook, Google, and others to force everyone to cross-link all their personal information. Soon after its launch in 2011, Google+ took a strong stand that only people willing to post under their real names would be welcome on the site, and (as one very minor consequence) I stopped posting there. Now, finally, Google+ has relented and will allow arbitrary user-chosen identities. They could have been more apologetic about it, but it's enough for me to return there.

I don't intend to change my Livejournal posting habits much, as I've been using my Google+ account for a somewhat different purpose: posting brief links to web sites that catch my attention and that I think might be of interest to my (mostly technical/academic) circles of contacts there. Here's a roundup of a dozen or so links I've posted so far (skipping the ones where I linked back to my LJ postings).

12 April 2014 @ 10:07 pm
When I last saw Tetsuo Asano, he was giving a research talk at WADS, and openly worrying that it might be his last one. We all thought it was because of mandatory retirement (still legal in Japan). But, it turns out, no. Instead, he's the new president of JAIST. Congratulations, Tetsuo!

I'll probably miss SoCG, in Kyoto this year, but for those who will be going, there will be an associated workshop in honor of Asano's 65th birthday.
20 December 2013 @ 12:37 pm
I first learned a couple days ago (via Jukka Suomela on Google+) that Elsevier has started sending takedown notices to individual researchers and the universities that employ them for putting copies of journal articles on their websites. Now I learn that the madness has spread to my own university (and to Harvard). Presumably, the issue is that the copies that the researchers put up were the final published journal versions, but still.

Free access to my works is much more important to me than their imprimatur. If I wasn't already boycotting Elsevier, this would certainly be enough by itself to make me want to. By this move, Elsevier has shown that it views itself only as a predator of, and not a part of, the academic research community.

In computational geometry, we're still supporting an Elsevier journal, Computational Geometry: Theory and Applications, by having officially endorsed special issues in it for conferences including SoCG and CCCG. I think it's time to stop doing that.
10 December 2013 @ 01:51 pm
The list of new ACM fellows is out. This year's batch includes two of my UCI colleagues (Rina Dechter and Padhraic Smyth), another former UCI colleague (Mark Ackerman), and theoretical computer scientists and algorithm researchers Mihir Bellare, Sampath K. Kannan, Jon Kleinberg, Madhav V. Marathe, Satish Rao, David P. Williamson, Moti Yung, and David Zuckerman. Congratulations, all!
Tags: ,
14 September 2013 @ 03:34 pm
Johns Hopkins violates academic freedom of faculty blogger, backs off when called on it. I knew there was a reason I kept this thing off-site...

Nationality-based blacklisting from academic publishing. Via Gowers. Given that I apparently live in a rogue surveillance state that tortures people, conducts undeclared cyberwar against the French, etc., this sort of collective punishment for government misbehavior troubles me. I suppose it's better than bombing them, though.

And, to make up for all that seriousness:

PingFS: keeping your data in the cloud by juggling raindrops.

You know how I recently posted that attaching labels to the things they label by curves or slanted lines would be better than axis-parallel polylines? This isn't what I meant. And many more bad ideas in information visualization, via MF.

Hexadecimal metric system. Complete with a new method of writing hexadecimal numbers, using a system of syllables for digits in which the consonant of each syllable tells you the digit value (in the obvious ordering q, b, p, v, f, z, s, d, t, j, c, g, k, y, x, w, h) and the vowel tells you what power of 16 it should be multiplied by.
10 March 2013 @ 01:34 pm
Predatory publishers that pretend to peer-review your papers (but really accept all comers to maximize their profits) lead to sad-but-funny situations like this one: Onion article about a children's menu found on the back of the original copy of the U.S. Constitution cited seriously by scientific article.

It may be entertaining, but it's not good for the literature for it to be cluttered up with this sort of cargo-cult imitation of research, and it's not good for universities and academics (and the students they teach) to be pressured into publishing this sort of junk in order to keep up a pretense of being a research university. (Also, before you say that impact factors will sort these things out, someone on the post I found this on has already commented that this journal's impact factor is pretty high; impact factors are easily manipulated and there's a lot of motivation for doing so.)
26 December 2012 @ 04:00 pm
While visiting relatives for Christmas, I heard a pretty damning account from one of my cousins (who works for a company that develops spam filtering software) about the uselessness of recent Ph.D.s in this area. If I understand the issue correctly, there is a pretty big mismatch between typical machine learning / information retrieval models of the spam filtering problem (a relatively static corpus of spam and ham messages, from which one must learn to filter the spam with the best possible combination of precision and recall) and the actual behavior of spammers (who are actively engaged in seeking out holes in spam filtering software, blasting as much spam as possible through any hole they find until it is patched or the system learns to filter it, and then moving on to the next hole).

In connection with this I found a paper by Tom Fawcett that made very similar points, nearly a decade ago. But it's easy to find recent and highly-cited works that don't take Fawcett's lessons to heart.

At the end of the 18th century and the beginning of the 19th, combinatorics flourished in German mathematics research, under the leadership of Carl Hindenburg. Later opinion has not been kind:

"ill-advised and purposeless modification"Sir Thomas Muir 1906

"of limited scope and restricted application"Encyclopaedia Brittanica 1910

"mired in the mathematical trivia by which the School itself was plagued"Manning 1975

"The faults of his [Euler's] time found their culmination in the Combinatorial School in Germany, which has now passed into oblivion"Cajori 1991

"thousands of pages filled with esoteric symbolism that must have impressed many nonmathematicians" — Knuth 2006

Knuth goes on to call Heinrich August Rothe "Hindenberg's best student", and says that his work is "not completely trivial", but cites as evidence only an algorithm for finding the successor and predecessor of a morse code sequence in lexicographic order.

Here are some Rothe's other contributions, from just one of his publications:

  • The first definition of the inverse of a permutation
  • A proof that the number of inversions of a permutation (the concept that Muir called "ill-advised and purposeless") is the same as for its inverse
  • A proof that the determinant of a matrix is the same as for its transpose
  • A diagram (the Rothe diagram) still used for visualization of permutations and inversions
  • The first definition of a self-inverse permutation
  • A simple recurrence formula for the number of self-inverse permutations

Not completely trivial?!

Yes, these results are easy nowadays, but in part that's because we learn about permutations from our beginning years of college, if not earlier. And where did what we learn about come from?

12 March 2012 @ 11:38 pm
If you've spent any time on Wikipedia you've probably noticed its red links, links on certain words and phrases that don't actually go to another Wikipedia article. They're supposed to flag topics where Wikipedia should have an article but doesn't, and encourage people to start editing a new article on the topic. And often they do work that way. But they also tend to accumulate, especially on lists, and once they start doing that they tend to include many words and phrases on topics that aren't ready to be made into articles.

So anyway, for the last few weeks (in my copious spare time) I've been clearing out the red from List of people by Erdős number. It was never intended to be comprehensive; that's for the Erdős number project or maybe for the collaboration distance calculator built into MathSciNet. Rather, it's just supposed to list the subset of people who both have (or should have) Wikipedia articles and have a small Erdős number. The #3 section of the list has been clear of red for a long time, and now the #2 is. Most of what I did was to remove names, but along the way I found quite a few people who (it seemed to me) should so clearly have articles that I made new ones. They are:

Baruch Awerbuch, Robert G. Bland, Hans Bodlaender, Derek Corneil, Danny Dolev, Rod Downey, Amos Fiat, Benedict Freedman, Nancy Freedman, Uriel Frisch, László Fuchs, Curtis Greene, John P. Hayes, David Jerison, Lila Kari, Anna Karlin, Jon Lee, Darrell Long, Heikki Mannila, Paul G. Mezey, Cris Moore, Bernard Moret, George Nemhauser, Nathan Netanyahu, Noam Nisan, Alfred van der Poorten, John E. Savage, Boris M. Schein, Norman Schofield, Eli Shamir, Mike Steel, Ileana Streinu, Subhash Suri, Stevo Todorčević, Dorothea Wagner, Stan Wagon, Tandy Warnow, Dominic Welsh, Moti Yung, and William S. Zwicker.

(There are one or two in there that I didn't make but expanded someone else's recently created one. And at least one of the names above is not actually on the Erdős number list.)

You might notice that they're not all the same length or level of detail. That has very little to do with how important I think these people are, and very much to do with how easy I found it to write about them. Also, the fact that I removed a name doesn't imply that I think that person hasn't met the Wikipedia inclusion criteria for articles on academics: there were quite a few other names that I removed from the list for whom I would support the creation of an article, but wasn't ready to do it myself.
09 March 2012 @ 04:22 pm
I just added two new Wikipedia articles on the Gesellschaft für Informatik (a major German computer science society) and their Konrad Zuse Medal.

In general I've found the English-language Wikipedia's coverage of German-language topics in the sciences to be somewhat spotty. Maybe it's because of the language barrier; maybe it's because the German-language Wikipedia is itself pretty good so German speakers don't feel the need to use or improve the English one. Whatever the reason, there's plenty more to be done in that direction.
03 January 2012 @ 03:56 pm
Some assorted links not big enough to make their own posts:

Read more...Collapse )
What acceptance rates should our conferences be aiming for, and what are the affects of those choices in the balance of papers that get into the conferences?

Mike Goodrich had an interesting recent post on Google plus arguing that, for reasons of scalability, academic conferences should aim for a stable year-to-year acceptance rate rather than (as seems more typical now) aiming for a stable year-to-year absolute number of accepted papers. In the comments to Mike's post, I raised a related issue, which is that (in my opinion) reduced acceptance rates lead to a greater emphasis on fashion and conventionality and a reduced fraction of speculative papers at the conference. I gave some reasons why I think that happens in the comment, but I thought I'd try to quantify that a little more precisely here.

Read more...Collapse )
07 June 2011 @ 01:08 pm
I ran across an odd story today (on a web site not known for its trustworthiness) about well-known algorithm researcher Baruch Awerbuch's mysterious disappearance a year or two ago. His publication record also shuts down at about the same time.

I'm sure it's an unrelated coincidence, but in retrospect some of his titles start to sound a little sinister: "Collaboration of untrusting peers with changing interests", "Collaborate with strangers to find own preferences", "Tell me who I am".