Sunday, December 30, 2007

A Good Example from Canada

I recently became aware of the Canada Research Chairs programme. That programme has been running since the year 2000, and aims at establishing 2000 research professorships—the so-called Canada Research Chairs—in universities across Canada by 2008. The Canada Research Chairs programme invests $300 million a year to attract and retain some of the world's most accomplished and promising minds.

I encourage the readers of this blog to have a look at the web site for the programme. There is a lot of interesting material there, and I cannot help but think that many countries would be well served by setting up a similar programme to attract the best possible scientists in all disciplines. Now, this is something well worth lobbying for in the coming year, isn't it?

If you do not have time to look at the web site I linked to above, here is my executive summary of the programme.

  • Each eligible degree-granting institution in Canada receives an allocation of Chairs. For each Chair, a university nominates a researcher whose work complements its strategic research plan and who meets the program's high standards.

    Three members of a college of reviewers, composed of experts from around the world, assess each nomination and recommend whether to support it.

  • Universities are allocated Chairs in proportion to the amount of research grant funding they have received from the three federal granting agencies: NSERC, CIHR, and SSHRC in the three years prior to the year of the allocation.

  • There are two types of Canada Research Chair:

    Tier 1 Chairs, tenable for seven years and renewable, are for outstanding researchers acknowledged by their peers as world leaders in their fields. For each Tier 1 Chair, the university receives $200,000 annually for seven years.

    Tier 2 Chairs, tenable for five years and renewable once, are for exceptional emerging researchers, acknowledged by their peers as having the potential to lead in their field. For each Tier 2 Chair, the university receives $100,000 annually for five years.

  • As you can see, there is a strong financial incentive to attract people to these endowed chairs!
  • Chairholders are also eligible for infrastructure support from the Canada Foundation for Innovation (CFI) to help acquire state-of-the-art equipment essential to their work.

  • If an institution's performance decreases relative to other institutions to the extent that the next recalculation of Chair allocations results in that institution's allocation being reduced, the Chairs Secretariat will reclaim, as appropriate, one or more of its unoccupied Chairs. Should all of the institution's Chairs be occupied, the secretariat will negotiate with the university on how best to reclaim the lost Chair(s).

Of course, the success of a programme like this one should be measured by the quality of the people who take up the chairs. (Italy has a similar programme already in place. You can read about it in a short article in Nature, with commentaries in the blog posts "The Runaway Brains" and "Brain Drain and Brain Gain".) You can look up the chairholders in all disciplines here. A quick browse through the names of the Canada Research chairholders in Information Technology and Mathematics makes me pretty sure that you'll find outstanding people in your area of interest.

Wouldn't it be great if we could convince our own ministries for education, university and research to set up a Research Chairs programme along the Canadian lines? Let's see what the new year will bring, but I do not hold my breath. I am already doing so waiting for the result of the pending research grant applications .

I wish a happy and productive 2008 to all readers of this blog.

Thursday, December 20, 2007

Workshop on Women in TCS

The department of CS at Princeton University is hosting a "Women in Theory" student workshop in Princeton on June 14-18, 2008. See for more details and list of confirmed speakers. (Via in theory.)

I am happy to see an initiative like this. In fact, I believe that we should have more events that highlight the achievements of women in TCS and that offer prospective students role models that they can look up to.

During my student days in Pisa, I thought that it was very natural for CS classes to be attended by roughly an equal number of men and women. I also followed a good number of classes where lecturers or TAs were female members of staff. Back then, I never thought that computer science was a male-dominated subject, and I had no reason to think so. Only much later, did I realize that what I thought was the norm was, in fact, an exception and, by the time I taught a class in Aalborg that was being attended by only one female student out of about 50 registered students, the lack of women in CS was not a surprise to me any more.

It is still my impression that Italy has a fairly substantial number of female (theoretical) computer scientists---at least compared to countries in Northern Europe. People often ask me for the reasons behind this phenomenon, and I am always at a loss to try and explain it.

Do any of you have a good explanation why countries like France and Italy seem to suffer less than others from the lack of women in subjects like CS? Could it be that things are getting worse there too?

Saturday, December 15, 2007

Computer Scientist: 21st Century Renaissance Man

The period from January till May each year is when faculty at the School of Computer Science at Reykjavík University try to make a determined effort to entice students to study our lovely discipline. (I know, we should do so all the year round, but somehow our good intentions do not become good deeds on a regular basis by themselves :-()

As part of our 2008 campaign, I have coauthored a short essay entitled Computer Scientist: 21st Century Renaissance Man. There is nothing particularly new in it, but I hope that it is readable and that it carries the message that CS is much more than most laypeople believe it is. Maybe some of you will find it useful for your own PR campaigns. Feel free to use it, if you think it may help.

You can draw some more inspiration from the items in our suggested-reading list. More essays of general interest may be found here. See also the excellent survey collection at Theory Matters.

Friday, December 14, 2007

Positions in Computer Science and Applied Maths at Reykjavík University

Some readers of this blog might be interested in the following job announcement. We are particularly interested in applicants in Computer Security, System Dependability, and related areas within the field of computer science. Moreover, Software Engineering is intended in a broad sense and we welcome applications from people working in, e.g., formal development techniques, model-based software development, and testing and verification.

In order to implement its ambitious strategy in research and teaching, the School of Computer Science at Reykjavik University seeks to hire faculty members for new academic positions. The following links point to pages with more detailed information about the vacant positions.

Applied Mathematics:
Computer Science:
Software Engineering:

In all cases,
position levels can range from assistant professor to full professor, depending on the qualifications of the applicant. Salary level is negotiable and relocation assistance is offered. The position is available immediately, but later starting dates can be negotiated.

Informal communication and discussions are encouraged, and interested candidates are welcome to contact the Dean of the School of Computer Science, Dr. Ari K. Jónsson (, for further information.

Wednesday, December 12, 2007

Registration for ICALP 2008 is Open

The registration page for ICALP 2008 and affiliated events went live yesterday evening at

We have done our best to keep the registration fees as competitive as we possibly could. The prices on the registration form are in ISK, but, by way of example, the regular early fee for a non-ICALP participant to a one-day workshop is around 77 euros, which become roughly 56 euros for somebody who registers also for ICALP. The early registration fee for ICALP is a little below 380 euros (including the excursion).

If you know that you will attend ICALP 2008, as you should :-), I strongly encourage you to book your flights and accommodation early. July is prime holiday time in Iceland, and you are more likely to get a good deal on your flights if you book as early as you possibly can.

Let me end, in the style of Numb3rs, by noting that ICALP 2008 is

13 workshops
8 days
5 invited speakers
3 tracks
2 prize awards
1 conference.

Thanks to my co-organizer Magnús M. Halldórsson for pointing out this "ICALP for fun" countdown and that this is going to be a Fibonacci-like ICALP!

Ranking of Excellent European Graduate Programmes in Natural Sciences

This report of the Centre for Higher Education Development (CHE), which was released about a week ago, may be of interest to readers of this blog. The CHE is a think tank for higher education. Based on international comparisons, they develop models for the modernization of higher education systems and institutions.

Their report develops a Ranking of Excellent European Graduate Programmes in Natural Sciences (viz. biology, chemistry, mathematics and physics), which is intended as an orientation guide for undergraduates, helping them find their way around European Higher Education while at the same time helping them to choose a suitable university for their graduate studies: Master’s and PhD.

At first sight, the report looks very well done, and for an Italian expatriate like me it is good to see that Italian institutions are doing rather well. I'd like to see a similar analysis carried out for programmes in computer science.

Let me try and provide a few remarks on the CHE report. In passing, I'll also offer some personal conclusions related to what the findings of this report may mean for a country like Iceland, which has great ambitions despite its tiny population.

Let me start by focusing on one message from the report that I find most important here (quoted from page 14 of the report). While reading the following text, bear in mind that "subject areas" refers to biology, chemistry, mathematics and physics, and not to a huge array of different disciplines.

"Another interesting finding is the fact that most institutions (33) are selected in only one subject area, 15 in two subject areas, 4 in three and also only 4 in all subject areas. If, even in the relatively closely connected academic fields of the natural sciences and mathematics, only 14% of the very top institutions in one geographic region are featuring three or all four subject areas, this can indeed be taken as an argument against institutionwide rankings."

Even though I enjoy reading the results of university-wide rankings, I believe that what should concern students choosing where to pursue their studies and funding agencies determining where to invest their research funds in specific disciplines is not the overall ranking of a university, but rather its excellence in the specific topic of interest. For this reason, I agree with the finding that subject-specific rankings are much more informative than institution-wide ones.

Of course, in general, a university that scores highly institution-wide won't have any very weak department. However, there may be, and indeed there are, universities that have peaks of true excellence in specific areas, even though they may not be world-beaters in many areas. If I were a prospective PhD student, I would prefer going to study in a department which is known to be top-class in the specific area of my interest rather than going to university X just because it has a globally good reputation. Quoting from the report:

"Prospective doctoral students are possibly less interested in the general performance of a faculty or department than in a specific research group. They usually have very clear ideas about the specialised topic on which they are focusing. Thus, it might be of some value for a student searching for a biology doctoral programme specialising in insects to know that the faculty at University A is excellent in its research output in this domain. However, it might be much more interesting for this individual to
learn that he could delve into honeybee studies in Würzburg's bee group. Or, a student in astrophysics might be attracted less by the overall performance of the Physics Department at the University of Copenhagen than by its research group focusing on dark matter and cosmology."

So my first conclusion is:

Conclusion 1. Our business as academic institutions is reputation. It is better to be known in a few selected areas than to be unknown in many. Icelandic universities should prioritize and place more resources in those areas where they can maintain or build a strong reputation internationally. The competition is growing stronger by the day; nobody stands still and we will need many more resources in the future just to maintain our present standing where we have one.

The second point that I'd like to pick out from the report is the minimum entry requirement for even entering the evaluation. The 3000 ISI publications from a institution over the evaluation period are indeed a very tall order for any Icelandic institution at this moment in time. Sometimes we pat ourselves on the shoulders and tell each other how well we are doing, and for very good reasons. However, we should never lose sight of the "big picture". A very good practice for any scientist is to remain humble, to know that there is a lot one does not know, and to keep in mind that there are very many strong scientists and departments out there.

As Socrates famously put it, "A wise man is one who knows he does not know." In this setting, I would translate this statement into something like this:

Conclusion 2. A wise rector/dean/head of department is one who knows that her university/faculty/department will need to improve its research quality and output considerably just to maintain its present status, no matter what its present strength is. The only way to do so is to hire the best possible researchers, to give them the best possible working environment and the freedom to follow their research interests. Research output will need to be considered when distributing research money to ensure that the most funding goes where the highest "interests" (read "quality publications in internationally recognized outlets") will be generated.

Two of the indicators considered by the CHE Ranking are
  • the percentage of international and female staff within the group of staff with a doctorate and
  • the percentage of female and international doctoral and master's students.

I am afraid that, despite our snow queens, we score badly on both of these fronts. Ranking measurements aside, it is of paramount importance for science in Iceland to nurture female talent and to seek actively to hire the best available female applicants. Mind you, I am against hiring female applicants just because of their gender. What I am saying is that our departments should have search committees who actively nurture connections with the best possible female applicants for positions and that outstanding female applicants should be given precedence when they are at least as good as the competition. Here the ministry could also chip in with some financial incentives to universities to hire outstanding female applicants. (I won't turn this into a conclusion though )

One may wonder whether some research groups from Icelandic universities can make it into the big league. The answer to this natural question that emerges from the CHE report is, I believe, positive. Look at the bottom of page 12 in the report. There you will read:

"Looking at table 2, the United Kingdom not only attains the largest number of gold medals but also the largest number of medals in total within the excellence group. Switzerland, with only three universities in this group, is in third place concerning gold medals and holds the largest relative percentage of gold medals: 16 out of 22 medals in the whole."

This is an outstanding, and not unexpected, performance of Swiss institutions. In fact, ETH Zurich is one of only four universities with gold medals in all of the subjects in the excellence group (the others being Imperial College, the University of Cambridge and the University of Utrecht)! How can Switzerland achieve this outstanding level of academic achievement? Rather than trying to answer this question myself, I will rely on higher authority and freely quote a few excerpts from an interview to the Italian mathematician Alfio Quarteroni (professor at the Ecole Federale Polytechnique de Lausanne and at the Politecnico di Milano) published in this book.

  • Switzerland has only two federal universities (ETH and EFPL).
  • These are two truly international institutions. To wit, about 70% of their professors are foreigners, and so are about 65% of the PhD students and about 33% of their undergraduates.
  • Each of the few and carefully chosen full professors in those institutions has the financial resources to build her own research team. For instance, Quarteroni's team has about 20 members. (As a curiousity, they helped build Alinghi, the boat that has won the last two installments of the America's cup.)
  • Quarteroni roughly says: "EFPL offers outstanding environmental and quality conditions that I have not found elsewhere. I have worked at the University of Minnesota, at Paris VI and, for shorter periods, in about 50 universities and research centres throughout the world, including NASA at Langley; well, on the basis of my personal experience, Lausanne is the place where I have been able to realize my goals in the simplest, fastest and most efficient way."

Conclusion 3. I let you draw your own conclusions as to what we need to do here in Iceland in order to approach the lofty heights that those Swiss institutions as well as several universities in Finland, The Netherlands, and Sweden have managed to attain. The above opinions of Quarteroni's raise many questions which I hope Icelandic university administrators will be willing to answer.

RU in the Guardian Education

Colin Stirling pointed out this article in the Guardian Education to me yesterday. This article is going to generate a little publicity for my current institution (Reykjavík University) and we can certainly do with that! It is also certainly true that Icelandic (academic) institutions feature more women in leading positions than elsewhere, and that their wages are comparable to those of equally qualified male colleagues. However, I am not so sure that Iceland is a particularly good example of a country that attracts good numbers of female students and members of staff in science and technology. We still have far too few women enrolling in computer science degrees, for instance, and my department employs one female professor and two female assistant professors. (Yes, we now have English web pages!) We will need to work very hard to try and change this situation, and this is one of our tasks for the future as far as recruiting is concerned both at student and staff level.

But enough grumping, let's enjoy our five minutes of fame in the British media, even though, as my rector Svafa Groenfeldt wrote to me,

"The interview was ok but as always the journalists take a bit of an artistic license when they quote what we said :-)"

Tuesday, December 11, 2007

A Cancellation Theorem for BCCSP

Wan Fokkink, Anna Ingolfsdottir and I have recently completed the paper A Cancellation Theorem for BCCSP, which is now available from the web page where Anna and I collect our papers.

The aim of this paper is to prove a cancellation result for the language BCCSP modulo all the classic semantics in van Glabbeek's linear time-branching time spectrum. The statement of this result is as follows.

Theorem. Let t and u be BCCSP terms that do not contain the variable x as a summand. Let <= be a preorder in van Glabbeek's spectrum. If t+x <= u+x then t <= u.

Apart from having some intrinsic interest, this cancellation result plays a crucial role in the study of the cover equations, in the sense of Fokkink and Nain, that characterize the studied semantics.

Fokkink and Nain proved the instance of the above theorem for failures semantics, with the aim to obtain an ω-completeness result for this semantics; their proof is rather delicate. To the best of our knowledge, failures semantics has so far been the only semantics in the spectrum for which the above result has been published. In our paper, we provide a proof of the above-mentioned property for all of the other semantics in the linear time-branching time spectrum. Despite the naturalness of the statement, which appears obvious, these proofs are far from trivial (at least for yours truly), and quite technical. I myself was really surprised by the amount of work we needed to do to prove such an "obvious" statement. (In case you wonder, the "obvious" statement is false in general. Consider, for instance, an algebra with carrier {0,1} and where the sum of any two elements is 1. Then the inequation y+x <= z+x holds, but y <= z obviously does not.)

I hope that some of the readers of this blog will find the paper worth reading. The techniques used in the proof of the cancellation theorem may also have some independent interest.

Sunday, December 09, 2007

Accepted Papers at FOSSACS 2008

The list of accepted papers for FOSSACS 2008 is out. I was in the PC for the conference, and I have to say that this year the number of very good submissions was substantially higher than the number of slots. (And this without counting the papers with which I had to declare a conflict of interests.)

Looking at the accepted papers, it is striking how many of them have French authors. In fact, France was the country with the largest number of authors of submitted papers this year (67 to be precise) , and the acceptance ratio for papers co-authored by French authors was high. By way of comparison, the country that had the second largest number of authors was the US with 29. Germany, Italy and the UK were roughly on a par with the US.

French TCS is hot, judging by these figures. LSV alone contributes at least five papers to FOSSACS 2008. This is quite a way of celebrating their tenth anniversary.

Thursday, December 06, 2007

ACM Fellows - 2007

I just had a look at the list of ACM Fellows for 2007. It has been a good year for TCS, and even concurrency theory and computer-aided verification are well represented in the list. Congratulations to Rajeev Alur, Lance Fortnow, Georg Gottlob, Rajeev Motwani, Amir Pnueli and all the other the new fellows.

On the subject of awards, I yesterday saw the call for nominations for the first CAV award. I have at least one person that I'd really like to nominate, but since I would prefer that person to be in cool Reykjavík for ICALP 2008 instead of sultry Princeton for CAV 2008, I guess I'll have to wait for one year before sending in my nomination :-) Who would you nominate for such an award? Note that
The cited contribution(s) must have been made not more recently than five years ago and not over twenty years ago. In addition, the contribution(s) should not yet have received recognition via a major award, such as the ACM Turing or Kanellakis Awards.
Unfortunately, the CAV organizers decided to fix the dates for their conference so that they coincide with the dates for ICALP 2008, which were known long before theirs. Time will tell whether this was an inspired decision on their part.

Wednesday, December 05, 2007

ICALP 2008: Second Call for Papers

The second call for papers for ICALP 2008 has just been posted to several mailing lists. The chances are that your mailboxes will be flooded by a good number of copies of the call for papers, but, in case this does not happen, you have been notified via this post :-) (In fact, I was quite amazed to discover that this modest blog is featured in the Theory of Computing Blog Aggregator, and so the odd post of mine might even be read by a CS theorist or two.)

In fact, submissions to ICALP 2008 are already open! To submit, please follow this link. Registration for the conference and affiliated workshops will be open very soon, allowing prospective participants to book flights and accommodation at a decent price. Iceland is a hot tourist destination in July.

Tuesday, December 04, 2007

ICALP 2008: Co-located Events

The list of events that will be co-located with ICALP 2008 (6-13 July, Reykjavík, Iceland) is now available. We received a record number of workshop proposals, and the number of affiliated events witnesses the interest in visiting the land that hosts me right now.

A second call for paper for ICALP 2008 will be posted very soon. Sharpen your pencils, and submit your best paper to the conference!

Sunday, December 02, 2007

10 Years of Verification in Cachan: Part I

On November 26 and 27, Anna and I were in Paris for 10 Years of Verification in Cachan, a two-day workshop organized by the Laboratoire Spécification & Vérification (LSV) of the ENS Cachan to celebrate its 10th anniversary. The workshop was centered around two special award ceremonies honouring two very good colleagues and friends of ours: Patricia Bouyer received CNRS's 2007 Bronze Medal for Computer Science (Monday 26th November), and Kim G. Larsen became Doctor Honoris Causa at ENS Cachan (Tuesday 27th November).

Despite being very busy and getting nowhere fast, we felt that we really ought to make the trip to Paris for this event, to which the organizers had kindly invited us to contribute talks. We were visiting professors at LSV in May 1998, when that laboratory was in its infancy, and we have very fond memories, both scientifically and socially, from that stay. In fact, our connection with LSV started informally long before that time when François Laroussinie and I shared an office in Aalborg for about a year starting from the autumn 1994 (when BRICS started its activities).

Today, there is little doubt that LSV is one of the hotbeds of TCS research in the Paris area, where there is really no shortage of talent and of extremely strong CS departments covering the whole gamut of TCS research. According to Philippe Schnoebelen, the present director of LSV, the centre now has about 40 members, and since its inception it had graduated 33 PhD students, seven of whom have been hired by CNRS. This is just one of the many indications of the success achieved by LSV over the first ten years of its existence. To my mind, another definite sign of impact is the number of former members of the laboratory who have taken up high-profile academic positions elsewhere. Here is what I could find on the LSV web site.
The workshop was a really enjoyable event. We had a great time, listened to some excellent talks, met a lot of colleagues and friends, and tasted some very good food. The organization was simply superb, thanks to the sterling efforts of Philippe Schnoebelen, Thomas Chatain, and Stéphanie Delaune.

Apart from my presentation, which ended the event, the two-day workshop featured talks by André Arnold, Pierre Wolper, Kim G. Larsen, Claude Kirchner, Marta Kwiatkowska, Michel Bidoit, Patricia Bouyer, Anna Ingólfsdóttir, Wolfgang Thomas, and Colin Stirling. This was really an embarrassment of riches, and I learned a lot from all of the talks---even from the two delivered in French :-) The quality of the presentations by these colleagues was invariably high, and the talks offered very accessible introductions to several areas of research covered by the members of LSV.

It would take way too long to report on all of the presentations. In this post and in subsequent ones, I'll therefore limit myself to recalling a few opinions and trivia that I heard at the workshop.

In his talk 25 years of automata and verification, Pierre Wolper went on record as saying that "Complexity, as traditionally measured, is not very relevant in verification." To wit, in his talk he pointed out that verification algorithms with high worst-case complexity turn out to perform well in practice and are widely used. Prime examples are automata-theoretic algorithms for LTL model checking as well as those implemented in the tool MONA, which implements decision procedures for the Weak Second-order Theory of One or Two successors (aka WS1S/WS2S)---a theory that is not elementary-recursive, as shown by Albert Meyer in this seminal paper. On the other hand, he presented an example from his own work yielding efficient automata-theoretic algorithms for CTL model checking, which are not used in practice. His conclusion was that one cannot trust complexity results. (I myself have mixed feelings about this opinion of Wolper's. Maybe I'll devote a post to this topic when life is less hectic. In the meantime, I'd love to hear your opinion.)

Pierre Wolper also said that his LICS 1986 paper An Automata-Theoretic Approach to Automatic Program Verification (Preliminary Report) with Moshe Vardi, which eventually won the LICS Test-of-Time Award and formed the basis for their paper that won the Gödel prize in 2000, had been rejected by two or three conferences before being accepted at LICS 1986! He also recalled the following sequence of reactions by Gerald Holzmann to their automata-theoretic algorithms for LTL model checking:
  1. "It must be wrong!"
  2. "It is impractical!"
  3. "It does not fit into SPIN!"
Eventually, the algorithm was implemented in SPIN, showing the power of elegant ideas in practice.

At the end of his talk, Pierre called for renewed efforts in implementing automata. I keep telling my students that automata are the most basic computational model in computer science, and I cannot help but share Pierre's call to arms.

I hope to report on a few other talks from the workshop when I have managed to catch up with a few of the items on my to-do list.