Brief review of the Handbook of Knowledge Representation

The new Handbook of Knowledge Representation edited by Frank van Harmelen, Vladimir Lifschitz and Bruce Porter [1] is an important addition to the body of reference and survey literature. The 25 chapters cover the main areas in Knowledge Representation (KR), ranging from basic KR, such as SAT solvers, Description Logics, Constraint Programming, and Belief Revision, to specific core domains of knowledge, such as Spatial and Temporal KR & R, and Nonmonotonic Reasoning, to shorter ‘application’ chapters that touch upon the Semantic Web, Question Answering, Cognitive Robotics, and Automated Planning.

Each chapter roughly follows the approach of charting the motivation and problems the research area attempts to solve, the major developments in the area over the past 25 years, important achievements in the research, and where there is still work to do. In a way, each chapter is a structured ‘annotated bibliography’—many chapters have about 150-250 references each—that serve as an introduction and a high-level overview. This is useful, for instance, if your specific interests are not covered in a university course but have a thesis student and you would want him to work on that topic, then the appropriate chapter will be informative for the student not only to get an idea about it but also to have an entry point as to which further principal background literature to read; or you are a researcher writing a paper and do not want to put a Wikipedia URL in the references (yes, I’ve seen papers where authors had done that) but a proper reference; or you are, say, well-versed in DL-based reasoners, but come across a paper where one based on constraint programming is proposed and you want to have a quick reference to check what CP is about without ploughing through the handbook on constraint programming. Comparatively with the other topics, anyone interested in ‘something about time’ will be satisfied with the four chapters on temporal KR & R, situation calculus, event calculus, and temporal action logics. Clearly, the chapters in the handbook on KR are not substitutes for the corresponding “handbook on [topic-x]” books, but they do provide a good introduction and overview.

Some chapters are denser in providing a detailed overview than others (e.g., qualitative spatial reasoning vs. CP, respectively), however, and yet other chapters provide a predominantly text-based overview whereas others do include formalisms with precise definitions, other axioms, and theorems (Qualitative Modelling, Physical Reasoning, and Knowledge Engineering vs. most others, respectively). That most chapters do include some logic comes as no surprise for the KR researcher but may be for the novice or a searching ontology engineer. For the latter group, and logic-sceptics in general, there is a juicy section in chapter 1, “General Methods in Knowledge Representation and Reasoning”, called “Suitability of Logic for Knowledge Representation” that takes on the principal anti-logicist arguments and the about 6-page long rebuttal of each complaint. Another section that can be good for heated debates is Guus Schreiber’s (too) brief comment on the difference between “Ontologies and Data Models” (chapter 25), which easily can fill a few pages instead of the now less than half a page used for arguing there is a distinction between the two.

Although I warmly recommend the handbook as addition to the library, there are also a few shortcomings. One may have to do with the space limitations (even though the book is already over 1000 pages), whereas the other one might be due to the characteristics of research in KR & R itself (to some extent at least). They overlap with the kind of shortcomings Erik Sandewall has mentioned in his review of the handbook. Several topics that are grouped under KR are not, or very minimally, dealt with in the book (e.g., uncertainty and ontologies, respectively) or in a fragmented, isolated, way across chapters what perhaps should have been consolidated into a separate chapter (i.e., abstraction, but also ontologies). In addition, within the chapters, it may well occur that some subtopics are perceived to be missing from the overview or mentioned too briefly in passing (e.g., mereology and DL-Lite for scalable reasoning), but this also depends on one’s background. On the other hand, the chapters on Qualitative Modelling and Physical Reasoning could have been merged into one chapter.

The other point concerns the lack of elaboration on real life success stories as significant contribution of that topic that a KR novice or a specialised researcher venturing in another sub-topic may be looking for. However, the handbook charts the research progress in the respective fields, not the knowledge transfer from KR research output to the engineering areas where the theory is put to the test and implementations are tried out. It is a philosophical debate if doing science in KR should include testing one’s theories. To give an idea about this discrepancy, part III of the handbook is called “Knowledge Representation in Applications” (emphasis added), which contains a chapter, among five others, on “The Semantic Web: Webizing Knowledge Representation”. From a user perspective, including software engineers and the most active domain expert adopters (in biology and medicine), the Semantic Web is still largely a vision, but not yet a success story of applications—people experiment with implementations, but the fact that there are people willing to give it a try does not imply it is a success from their point of view. Put differently, it says more about the point of view of KR&R that it is already categorised under applications. True, as the editors note, one needs to build upon advances achieved in the base areas surveyed in parts I and II, but is it really ‘merely’ ‘applying’, or does the required linking of the different KR topics in these application areas bring about new questions and perhaps even solutions to the base KR topics? The six chapters in part III differ in the answer to this question—as in any healthy research field: there are many accomplishments, but much remains to be done.

[1] Frank van Harmelen, Vladimir Lifschitz and Bruce Porter (Eds.). Handbook of Knowledge Representation. Elsevier, 2008, 1034p. ISBN-13: 978-0-444-52211-5 / ISBN-10: 0-444-52211-5.


Editorial freedoms?

Or: on editors changing your article without notifying (neither before nor after publication).

The book The changing dynamic of Cuban civil society came out last year right before I went to Cuba, so I had read it as a preparation, and, it being a new book, I thought I might as well write a review for it and see if I could get it published. The journal Latin American Politics and Society (LAPS) was interested, and so it came to be that I submitted the book review last July and got that review accepted. Two days ago I was informed by Wiley-Blackwell, the publisher of LAPS, that I could download the offprint of the already published review: it had appeared in LAPS 50(4):189-192 back in the winter 2008 issue.

The published review is for “subscribers only” (but I’m allowed to email it to you) and to my surprise and disbelief it was not quite the same as the one I had sent off to the LAPS book review editor Alfred Montero. They had made a few changes to style and grammar, which, given that English is not my mother tongue, was probably warranted (although it would have been appropriate if I were informed about that beforehand). There are, however, also three significant changes to the content. More precisely: two deletions and one addition.

The first one is at the beginning, where an introduction is given on what constitutes ‘civil society’. Like in the book, some examples are given, as well as the notion of a ‘categorisation’ of organisations. The original text (see pdf) is as follows:

According to this description, hobbies such as bird watching and playing rugby is not part of civil society, but the La Molina against the US base in Vicenza and Greenpeace activism are. In addition, one may want to make a categorization between the different types of collectives that are part of a civil society: people have different drives or ideologies for improving or preventing deterioration of their neighborhood compared to saving the planet by attempting to diminish the causes of climate change.

This has been trimmed down to:

According to this description, hobbies such as bird watching and playing rugby are not part of civil society, but Greenpeace activism is. In addition, one may want to make a categorization between the different types of collectives that are part of a civil society: people have different drives or ideologies for improving or preventing deterioration of their neighborhood, compared to saving the planet by attempting to diminish the causes of climate change.

A careful reader may notice that there is a gap in the logic of the examples: the No Dal Molin activism against the US base is an example of NIMBY-activism (Not In My BackYard), referred to in the second sentence but the example in the first sentence is missing. There being no example of this type in the book, I felt the need to give one anyway. Perhaps if I would have used the for the US irrelevant NIMBY-activism against the TAV (high speed train) it would have remained in the final text. The activism of Molin, however, is a much more illustrative example of the interactions between a local grass-roots civil society organisation and both national and international politics, and how the so-called ‘spheres of influence’ of the actors have taken shape.

The addition is a verb, “to act”. The original:

Christine Ayorinde discusses both the historical reluctance of the, until 1992, atheist state against religious groups—used as counterrevolutionary tool primarily by the U.S. in the early years after the Revolution—and the loosening by the, now constitutionally secular, state …

The new sentence:

Christine Ayorinde discusses both the historical reluctance of the atheist state (until 1992) to act against religious groups—used as counterrevolutionary tool primarily by the United States in the early years after the revolution—and the loosening by the now-constitutionally secular state, …

But it is not the case that the state was reluctant to act against religious groups; they were reluctant and hampering involvement of foreign religious groups because it was used by primarily the US as a way to foment dissent against the Revolution.

The second deletion actually breaks a claim I make about the chapters in the edited volume and weakens an important observation on the operations of civil society organisations in Cuba, and of foreign NGOs in particular.

The original:

A personal experience perspective is given by Nino Pagliccia from the Canadian Volunteer Work Brigade (Chapter 5). This is a fascinating chapter when taken in conjunction with Alexander Gray’s chapter that analyses personal perspectives and changes in procedures from the field from a range of civil society actors (Chapter 7). … Pagliccia’s, as well as the representative of Havana Ecopolis project’s—Legambiente-funded, which is at the green-left spectrum of the Italian political arena—documented experiences of cooperation in Cuba have the component of shared ideology, whereas other representatives, such as from Save the Children UK, talk about shared objectives instead even when their Cuban collaborators assume shared ideology. Notably, the latter group of foreign NGOs report more difficulties about their experiences in Cuba.

How it appears in the published version:

A personal perspective is given by Nino Pagliccia, from the Canadian Volunteer Work Brigade (chapter 5). This is a fascinating chapter when considered together with Gray’s chapter 7, which analyzes personal perspectives and changes in procedures from a range of civil society actors. … Pagliccia’s documented experiences of cooperation in Cuba have the component of shared ideology, whereas other representatives, such as those from Save the Children UK, talk about shared objectives instead, even when their Cuban collaborators assume the former. Notably, the latter group of foreign NGOs report more difficulties in their experiences in Cuba.

But the reference to Havana Ecopolis comes from Chapter 7. In fact, of the interviewees, he was the only one really positive about the experiences in the successful foreign-initiated project/NGO, which made me think back to Pagliccia’s Workers Brigade and solidarity vs. charity. I wondered where the funding of Havana Ecopolis came from, Googled a bit, and arrived at the Legambiente website (project flyer). Needless to say, also openly leftist organisations had positive experiences on collaboration; but in analyzing effectiveness of foreign NGO involvement, unveiling the politically-veiled topical NGOs is a distinguishing parameter. Moreover, it is an, informally, well-known one with respect to Cuba’s reluctance of letting foreign NGOs into the country. Thus, it explains why the Havana Ecopolis experience stood out compared to the other documented NGO experience in Cuba. But now, in the revised text, the “Notably, the latter group … more difficulties …” sounds a bit odd and not backed up at all. They even toned down Pagliccia’s contribution from “A personal experience perspective” to “A personal perspective”: there surely is a difference between being informed by having spent some time in Cuba working side-by-side with the Cubans and just having a perspective on Cuba without having a clue what the country is like; now it reads like ‘yeah, whatever—opinions are like assholes: everybody’s got one…’. Note that when one reads the book, one sensibly can make the link between the data and analysis presented on solidarity vs. charity vs. cooperation and the shared-ideology vs. shared-objectives NGOs (ch5 & 7). Rests to make a categorisation of foreign NGOs and conduct a quantitative analysis to back up the obvious qualitative one.

I hope that this case is an exception, but maybe it is the modus operandi in the humanities that things get edited out. It certainly is not in computer science, where only the authors can fiddle a bit with the text when a paper is accepted, and even less so in the life sciences where, upon paper acceptance, thou shalt not change a single word.

UPDATE (22-3-2009): the current status of the contact I had with the LAPS editorial office is that the book review editor, Alfred Montero, did not change anything, but that that happened during copyediting by the managing editor, Eleanor Lahn. She has provided me with an explanation why the changes were done, which has a curious argumentation to which I have replied. This reply also contains a request for clarity and consistency in the procedure (now the book editor assumes the copyeditor contacts the author, whereas the copyeditor normally does not do so), but I have not yet received a response on that email.

Celebrating women’s achievements

Today is International Women’s Day to celebrate the achievements of women across the world during the ages. So I will not digress on unpleasant experiences (due to achievements), but I will highlight some positive aspects.

Aside from a list of famous women in history that spans a range of areas also beyond science and engineering (heads of state, philosophy, movie directors etc.):

  • From the science perspective, there’s the list of Female Nobel Laureates, including the latest addition (2008) with Françoise Barré-Sinoussi in Physiology or Medicine and the, thus far, unbeatable Marie Curie with two prizes in different disciplines (1903 and 1911 in Physics and Chemistry, respectively) whilst raising a Nobel Prize-winning daughter (Irène Joliot-Curie, Chemistry 1935). More notable female scientist are listed for the physical science and life science and medicine, among the many sources.
  • From the International Women’s Day website, there are interesting bits of information about women in Business/Finance, Arts, and Innovation, among others. Women do not lack engineering creativity: among others, Josephine Cochran presented the first dishwasher at the World Fair 1893, Mary Anderson got her patent for windshield wipers in 1903, Kevlar was patented by Stephanie Kwolek in 1966, and last, but not least, the world’s first computer programmer and inventor of its programming language to get Babbage’s machine to do something, Ada Lovelace.

More recently than Ada Lovelace, we have other famous women in computing such as Grace Hopper and Anita Borg. Maybe I should make a list of currently living notable women in AI and its applications. For instance, Manuela Veloso has won Robocup several times thanks to both significant theoretical and engineering contributions, Ulrike Sattler and Deborah McGuinness in Description Logics, Sylvie Spreeuwenberg as cofounder of the company Librt on business rules, Carole Goble as e-science manager, and Midori Harris as principal curator of the Gene Ontology.

But I do not know intimately all sub-areas in AI, let alone the whole of computer science and engineering; you have any suggestions to include in the list?

UPDATE (11-3-2009): Rina Dechter in automated reasoning, Francesca Rossi on constraints, and Gigina Aiello in KR, planning and robotics. Barbara Liskov for her achievements in programming language design  (and more, see also the Turing Award 2008 press release).

back to work

So I made it back to a rainy Italy, and despite working ahead before attending Informatica 2009 and the holidays, a lot of work has been piling up nevertheless; most of the work is fun to do though, but maybe I’m in a minority when I admit I’m fine with paper deadline season (finally getting the paper done and out for review etc).

There were a few surprises when I went online again, like that my previous post about the VIP session was, and still is, suffering from spam attacks, which could be due to the topic or just because it was the last post for a while; time will tell. I did add a few photos and a link to Ramirez’ speech there (more photos from Cuba will appear on my website). The amount of visits to my blog was about the same as the previous months, as if it does not make any difference if I post something or not. But I will ignore that fact, for a while at least.