Thursday, May 17, 2012

Meetings/Conferences/Workshops/Seminars- whats in a name?

In June 11-14 will be a new workshop: Algorithmic Frontiers.




How many venues do we have for meetings?
  1. What the call themselves:
    Meetings (e.g., MATHFEST), Conferences (e.g., STOC), Workshops (Barriers), Seminars (e.g., Dagstuhl), Tutorials, Lunches. More?
    (six options)
  2. Criteria for getting a paper in: Refereed (e.g., STOC): lightly refereed (I think MATHFEST), unrefereed, talks-by-invite-only (Algorithmic Frontiers, Barriers)
    (four options)
  3. Participants: Open (most)or by-invite-only (Dagstuhl and Bertinoro) (two options)
  4. Size: This is more informal. However, CCC is small (100), STOC is larger (around 400), FCRC larger still, and Supercomputing is expecting 11,000. Medical conventions can get around 20,000.
    (five options, though could be more or less depending on your mood.)
  5. Variety of activities: A venue can have any combination of the following: contributed talks (unrefereed), refereed talks (typical STOC), invited talks, rump sessions,
    tutorials, workshops, short courses. (128 combinations, though in reality only about 5 options actually happen, so I'll take it as 5)
  6. Length: Number of days can be anything from 1 day to 2 months. However, I don't think all 60 options really exist. I've seen 1,2,3,4,5 days, 1 week, 2 weeks, 1 month, and 2 months. nine options.
  7. Expense: Either expensive or VERY expensive.
So that would be 6x4x2x5x5x9x2. That's a lot! Of course its far far less since, for example, an invite-only gathering can only have invited talks. I would guess its more like 5 types. And some are inconsistent (e.g., STOC sometimes has tutorials and sometimes doesn't).

Algorithmic Frontiers seems to be a 4-day open workshop that has invited talks only. I don't know how big it will be but I would guess between 100 and 200.

Do the gatherings that we go to work? As my Software engineering friend Jim Purtilo often says If you don't know your goals you are not going to achieve them. So, what are the goals? Ultimately to help both us as individuals and us as a community in our research. The hope is we learn things and get inspired to work on problems. And these can be done by the formal talks in the ballroom and informal talks in the hallways. Does this happen? Yes. Is it cost effective (not just money but time)? Debatable, as this and other blogs have debated. Here are my experiences. What are yours?
  1. DAGSTUHL SEMINARS. These are specialized one-week long meetings by
    invitation only. The talks need not be on the latest/greatest thing and hence are understandable. (I've been to DAGSTUHL- Complexity 3 times.)
  2. Bertinoro is similar to Dagstuhl. I've been to the RATLOCC 2011 and
    RATLOCC 2009 which are on Ramsey Theory and Logic. Here there were even more talks
    that were surveys or historical-perhaps because math moves slower than computer science.
    If the talks were on the INTERSECTION Of Ramsey Theory and Logic then it would be too specialized.
    (I've worked in both, but not quite together.)
    As is, its a nice mix.
    But the main point- I understood the talks.
  3. The Center for Intractability sponsors workshops which anyone can go to
    but the speakers are picked by them. I've been to one of the Barriers workshops and it was very good. The speakers have more time then at conferences,
    which is a plus. The Algorithmic Frontiers workshop seems to be in this model.
  4. The last few CCC's and STOC's that I've gone to I have enjoyed and gotten stuff out of, but not as much as the smaller venues.
    Partly because the talks are shorter.
    which is a plus. The Algorithmic Frontiers workshop seems to be in this model.
  5. MATHFEST is nice in that there is a VARIETY Of activities- workshops, seminar, tutorials, invited talks.
    Very large which is both good (that's why they can have all of these things and bad (I never met the same person twice).
  6. One of my colleagues, Jeff Hollingsworth, is organizing SC12, Supercomputing 2012.
    This will have 11,000 people at it. The program committee has over 100 people
    on it. This seems... large. They seem to have a variety of activities
    so it more like MATHFEST.
  7. Of course the talks are only part of the reason to go to these things. Even so, for me they are a big reason.

What venues to YOU get the most out of? Why or why not?

Wednesday, May 16, 2012

Gödel Prize

The ACM announced the 2012 Gödel Prize awardees, three seminal papers in algorithmic game theory. The prizes themselves will be presented at ICALP in Warwick in July.

Elias Koutsoupias and Christos H. Papadimitriou: Worst-case equilibria, Computer Science Review, 3(2): 65-69, 2009.

Tim Roughgarden and Éva Tardos: How Bad Is Selfish Routing?, Journal of the ACM, 49(2): 236-259, 2002.

Noam Nisan and Amir Ronen: Algorithmic Mechanism Design, Games and Economic Behavior 35: 166-196, 2001.

The first paper introduced the price of anarchy. The second applied price of anarchy to routing problems. The third applied algorithmic techniques and competitive analysis to auctions.

Congrats to all the winners.

Monday, May 14, 2012

Wall Street Complexity

There is much blame to go around for JPMorgan Chase's two billion dollar loss last week but part of that blame came back to us. In a New York Times web piece, How Moore’s Law Affects Wall St. Trading, Quentin Hardy argues
Faster, cheaper computing makes it possible to create more and better models for calculating cash movements, which can be turned into trading instruments. Areas like leasing, mortgages and project finance have exploded – as has the entire financial derivatives market — thanks to cheap computing...
Soon, it becomes nearly impossible to say what is going on where, and you get events like the 1998 blow-up at Long Term Capital Management, the creation and destruction of the subprime mortgage market in 2008 and perhaps even the “flash crash” in 2010. JPMorgan’s loss seems to be the latest in that series.
I've argued the dangers of reducing computational friction before. But here computational complexity comes in a different way. A derivative is just a function of current and future security prices. But a derivative complex enough can have a behavior that even its creator cannot understand. The Clay Math Institute offers a million dollars to settle "P v NP" but it cost Chase two billion.

Thursday, May 10, 2012

So THATS why the 17x17 challenge was so hard. Or maybe not.

On November 30, 2009 I posted the famous 17x17 challenge:

(Paraphrase) Find a 4-coloring of the 17x17 grid that has
no monochromatic rectangles. For $289.00. It was solved in 2012
by Bernd Steinbach and Christian Posthoff (I posted about it
here
and will post their paper when they make it it is public, which should be soon.)
Even though it was solved, it seemed to be a hard problem.

On April 28, 2010 (before the problem was solved)
I wondered WHY it was so hard and posted the following question:

(Paraphrase) Consider the following problem:
Given (N,M,c,f) where f is a partial c-coloring of NxM,
can f be extended to a total c-coloring of NxM (without mono rectangles)?
Is this problem NP-complete?


Kevin Lawler emailed
me a sketch of a proof recently! So YES, it is NP-complete!
I cleaned it up, wrote it up, and put in a few other things, and the paper is
here.
(We will be posting to arXiv after we get comments from this blog.)

  1. Does this really show why the 17x17 challenge was hard?
    Not really since the 17x17 challenge is just one instance.
  2. Does this show that grid coloring problems are hard in general?
    Not really since the case we are really interesting in is where
    f is the empty function. While we do not believe this case is
    easy, we have not ruled this out.
  3. What can we show about the algorithmic complexity?
    The problem is FPT. For fixed c its in time poly(N,M)+O(cc4).
This is a problem for hardness-of-Ramseyian numbers in general. While it seems as if computing (say) Ramsey Numbers is hard, there is no real proof of this. Related problems have been studied by Marcus Shaefer here.
While this work is very interesting
it is NOT the same as showing that finding Ramsey Numbers is hard.I suspect that to prove such things we need a new framework for
lower bounds.


Monday, May 07, 2012

Paying to Publish

You proved a nice theorem, wrote up the paper and submitted it to a major computer science conference. Your paper was accepted! Congratulations. Now pay up.

An author of every paper accepted at a CS conferences is expected to present that paper at the conference. To do so requires at the least paying the registration fees, travel and lodging to go the the meeting. That can easily run one to three thousand dollars (or more) depending mostly on how far you need to travel.

You can use grant money for these expenses. Some conference offer support to those who need it, particularly students. CS departments will often help out if needed. Sometimes people pay out of their own pockets and, in any case, the funds come from limited pots that could have been used for other purposes.

In the "old days" this was less of a problem. There were only one or two conferences relevant to one's field and you were probably going to those conferences anyway. Now as the field has grown and it has been harder to get your papers published in the strongest conferences, you may find yourself traveling just to give the talk. Even many major conferences don't draw many attendees who don't have papers in the conference.

We haven't seen an outcry of these expenses, say compared to the outcry over the cost of digital library subscriptions. Perhaps we consider attending the conference a "reward" for getting published.

We could just eliminate the conferences and publish the proceedings and post videos of talks, made at the home institutions, saving the field huge amounts of money. Then we could actually choose to attend conferences to meet people in our field instead of just talking at them.

Note: Elchanan Mossel had a similar observation in a comment on a recent post.

Friday, May 04, 2012

Is it well known that we need to redefine well known?

A LONG time (so long ago I was a guest poster, not a co-blogger)
I posted
about how calling things that are on You-Tube rare is odd
since ITS ON YOU-TUBE! ANYONE in the world can look at it!
I now have a Contrasting thought: Can something be
well known if its not easily found on the web?

Last week I
posted
a proof that the intersection of a CFL and a REG lang
is CFL that did not use PDA's. I thought it was NOT new and indeed, the
comments politely gave me the proper reference.
So far, so good. But wait--- some of them called the proof Well Known.
Can a proof be well known if its not on the web?
The notion of a proof being well known has always been problematic
since one wonders what the scope is.

  1. Addition
    being commutative is well known but might not
    to my 5-year old niece.
    Someone emailed me that I should take this opp to teach her
    about noncommutative algebras.
  2. Binary search is well known but might not be known to my (then)
    8 year old great nephew.
    Some said I should use this opp to teach him logarithms.
  3. Induction is a well known technique but it still puzzles some undergraduates.i
  4. The poly vdw theorem
    is well known among mathematically inclined
    high school students in Maryland but
    is not even that well known among combinatorists.
The point really is well known to who?. But now with the web we can ask a more focused question: Can you find it easily? The proof I posted was not one that I found on the web. So here is what I want your thoughts on:
  1. Should we redefine our definition of
  2. If I were to make an article out of the three short notes on CFL's
    that I posted about, and submit to Math Archives,
    would that help the problem of what is easy to find
    or would it just clutter up Math Archives making things hard to find.
    (I would of course provide all references and make NO claim to
    originality.)
  3. Should I post to Wikipedia?
  4. Will the web ever replace
    asking someone who knows stuff?

Thursday, May 03, 2012

Microsoft saves the Yahoo NY Researchers

I started working with David Pennock on prediction markets back when we both were at the NEC Research Institute in New Jersey a decade ago. After a major reorganization the dropped basic research from their mission, I went back to academics but David stayed in industry research first at Overture which soon was swallowed up by Yahoo. He ended up at Yahoo Research New York in a small but amazingly strong research lab including machine learning theorist John Langford and social scientist Duncan Watts. But with a new Yahoo CEO and Prabhakar Raghavan and Andrei Broder's departures for Google, it  became clear that the days of Yahoo research were numbered. 

Today Microsoft announced that they are hiring 13 researchers from the Yahoo lab including David, John and Duncan as they start a new Microsoft Research Lab in New York, initially led by Microsoft New England director Jennifer Chayes. Lots of nice coverage from the New York Times, All Things D,  blog posts from Jennifer and John, and a pictorial take from Chris Maase. Not the first time Microsoft has done something like this, Microsoft Research Silicon Valley got its start by hiring several researchers from the old Xerox PARC.

I'm happy the Yahoo researchers found a great home but I also mourn the loss of yet another company abandoning basic research in computer science.

Tuesday, May 01, 2012

Berkeley Wins the Simons

As reported today in the New York Times, the Simons Foundation has chosen U. C. Berkeley to host the new Simons Institute for the Theory of Computing, a $6,000,000/year center for studying core theoretical computer science and its applications to other disciplines. There will be 70 researchers (faculty, postdocs, grad students) at any given time affiliated with the Institute.

This will be a game changer for CS theory.