Saturday, January 27, 2007

Stendhal - Rouge et Noir


It seems to be the time to write about the first big novel I have read this year...although I'm already 2 books ahead and otherwise I will loose track completely. As usual - and as I have read the book in German translation - I will write a short comprehension in english, but will discuss everything in German.
Stendhal a.k.a. Henri Beyle put the scenery of "Rouge et Noir" in the time of about 1830, the Bourbone restauration in France, and subtitled it as a chronicle of the 19th century - which was still young at his time. But, it was supposed to be a novel taking place right now...and not in the past. Julien Sorell, the unusual intelligent son of a simple wood cutter - at least as being a designated priest he could speak Latin and had an enormous memory that he showed when citing entire parts of the bible by heart (and in Latin) - got the job of a house teacher in the family of the local Mayor M. de Renal. He seduces Mdme. Renal - not really out of love, but more because of his ego - and to avoid a scandal he is forced to leave. He joins the priest seminar - which by the way is one of the most impressive written parts of the book - and finally succeeds in becoming the private secretary of Marquis de la Mole. The Marquis' daugther soon got an eye on Julien and finally - this really takes Julien some time and and also sophisticated strategies - they plan to marry because she became pregnat (by him...). Of course the Marquis is rather dissappointed about this misalliance. Then, he receives a letter written by Mdme. de Renal in which she warnes the Marquis de la Mole about Julien being an imposter, whose only goal is to make carreer out of seducing women in the families where he is put in. Julien also reads the letter and for revenge shoots Mdme. de Renal while she is attending at church. Although she recovers, Julien gets voluntarily adjudged and executed......

Die vorliegende neue deutsche Übersetzung von Stendhals Klassiker ""Rot und Schwarz" kann ich allen - egal ob Fan von französoscher Literatur des 19. Jahrhunderts oder nicht - nur wärmstens ans Herz legen. Das Buch ist überaus spannend und unterhaltsam geschrieben. Stendhals mitunter kurze und prägnante Art verzichtet auf ausschweifende Schilderungen der Schauplätze ohne jedoch das jeweils für diese typische außer Acht zu lassen. Üppig, intensiv und wohlüberlegt ausgefallen sind alle Dialoge. Man durchlebt die Höhen und Tiefen von Julien Sorells Dasein - auch wenn man seine Gefühle, seinen Antrieb heute nicht immer recht verstehen kann. Die französische Revolution, Napoleons Kaiserreich und die anschließende Restauration - auf die eine weitere Revolution folgen sollte - prägen das gesellschaftliche Bild, das Stendhal zeichnet. Der Karrierist und bürgerliche Emporkömmling wird ebenso scharf charakterisiert wie der alteingesessene Adel, der ewige Streit zwischen Jesuiten und Jansenisten verfolgt die Handlung wie das gerade im Entstehen begriffene Genre des Stutzers und modebewußten Dandytums. Und natürlich die Frauen...alle scheinen sie in Julien verliebt. Angefangen von der unscheinbaren Kammerzofe, über Mdme. de Renal, einer Kaffeehausangestellten, einer verwittweten Generalin, bis hin zur Marquise de la Mode...alle weiß Julien von sich einzunehmen...und zu enttäuschen.
Das Ende jedoch - laut Stendhal Bestandteil der dem Buch zugrundeliegenden wahren Begebenheit - bleibt mir rätselhaft. Wie bereits geschildert versucht Julien Mdme. de Renal in der Kirche zu ermorden und sieht danach, obwohl diese sich von ihren Verletzungen erholt und ihm vergibt, keinen anderen Ausweg, als sich dem Gericht zu überantworten und selbst auf seine Verurteilung zum Tode zu bestehen. Natürlich...nicht gerade ein 'Hollywood'-gerechtes Ende. Aber eindringlich und wirklich kurzweilig erzählt. Besonders hervorzuheben sind in dieser Ausgabe die vielen Zugaben. Neben einem ausführlichen Anhang mit Erklärungen und Anmerkungen Stendhals (die man im laufenden Text jeweils nachschlagen kann..) bietet die Ausgabe noch Entstehungs- und Wirkungsgeschichte, sowie Stendhals eigene Rezension des Werkes. Also: Lesebefehl!

Wednesday, January 24, 2007

SOFSEM - Day 4

Now we have snow....finally :) ...even a lot of it. It was snowing all day long, roads in Czech Republic and also in southern Germany were closed. Also Prague Airport was closed until the afternoon. But, I guess as far as I remember that are the more typical weather conditions for SOFSEM.
Anyway, the day started with a keynote of Tom Henziger about 'Games, Time, and Probability: Graph Models for System Design and Analysis'. He addressed three major sources of system complexity: concurrency, real time, and uncertainty. Concurrency can be modelled as a multi-player game representing a reactive system with potential collaborators and adversaries. Real time requires the system to combine discrete state changes as well as continous state evolution, while state changes - for uncertainty - also have to be modelled in a probabilistic way.
Unfortunately some of the presenters of the following contributed papers did not show up. Thus, the conference program was subject to several changes. In the afternoon the posters of the student research forum each had a short 5 minute presentation, followed by a poster exhibition and a lot of discussions. In the end, the participants should give a vote for the best poster presentation. My choice - which of course is completely subjective - was the poster of of Henning Fernau and Daniel Raible on 'Alliances in Graphs: a Complexity-Theoretic Study'.
In the late evening I was trying to look for my car, which was buried under the snow at the parking lot. Due to the wind the snow around the parking lot (and my car) was piled up almost half a meter...which made me think about the road conditions and the plan of driving home the next day....

Tuesday, January 23, 2007

SOFSEM 2007 - Day 3

Today started with a keynote given by Ricardo Baeza-Yates from Yahoo! Research on 'Mining Web Queries'. In particular he showed how to identify categories of user queries and how to use this information to create an appropriate ranking of the search results. Besides the already identified 'coarse' categories, such as, e.g., queries being 'informational', 'navigational', or 'transactional' (which means that the user wants to have (a) information about a specified topic, (b) a starting point for further research, or (c) a homepage related to the resource for transactional purposes (e.g. shopping)...), he addressed several graphs that can be compiled out of the search engine logfile, as e. g., URL cover graph, URL link graph, session graph...These graphs can be used for identifying polysemic expressions, similar or related queries, clusterings of queries, or even a (pseudo)taxonomy of queries.
Besides web query mining, he mentioned some interesting numbers concerning Yahoo, as e.g. that Yahoo administrates about 20 PetaBytes of Data with more than 10 TeraBytes of data traffic per day. But, on the other hand, he gave an estimation of the actual world knowledge and related it to the ammount of data managed by Yahoo today: given that a person creates about 10 pages of data concerning a distinct event, and if we estimate the number of events of about 5000 in a lifetime, and if we multiply that number by the world's population....we will end up with about 0,0057% of the 'world knowledge' currently being represented in Yahoo...

Monday, January 22, 2007

SOFSEM 2007 - Day 2


The second day of SOFSEM started with a keynote of Bertrand Meyer (maybe you remember Eiffel...) from ETH Zürich on 'Automatic Testing of Object-Oriented Software'. To enable automated testing, he referred the concept of 'contracts' being directly embedded in the classes of the Eiffel programming language. With a contract you are able to specify the software's expected behaviour (preconditions, postconditions, and invariants). which can be monitored during execution. In automated software testing, contracts may serve as test oracles that decide, whether a test case has passed or failed. He presented 'Auto Test' unit testing framework, which is using Eiffel contracts as test oracles. Auto Test is able to exercise all classes by generating objects and routine arguments. Also manual testing can be embedded as well as regression testing for failed test cases, which is implemented in a 'minimized' form by retaining only the relevant instructions.

For the rest of the second day contributed (refereed) paper presentations are scheduled. I will have to chair the first session of the 'emerging web technologies' track, which will be on XML technology. If there (or in any other session I attend) will be anything of interest, you will read it right here ... :)
So...Joe Tekli from the Université de Bourgogne presented a 'Hybrid Approach on XML-Similarity', which combined structural similarity of XML-Documents with 'semantic' arguments, i.e. tag names of different XML-documents are compared with the help of WordNet to compute some similarity measure. Quite an interesting application that can be build on, esp. regarding the semantic similarity aspect. But nevertheless, maybe we can use it for our MPEG-7 based video search system (OSOTIS).

Sunday, January 21, 2007

SOFSEM 2007 - Day 1


This year, after about 7 or 8 years, I am attending again the SOFSEM conference on 'Current Trends in Theory and Practice of Computer Science' (for the 2nd time). Maybe SOFSEM is not the most important of all the computer science conferences around, but it is rather original and has quite some history (i.e. it's tradition dates back more than 30 years...). SOFSEM means SOFtware SEMinar, and this already gives some hint about its originality. Starting from a winter lecture with only limited international attendance it has developed to an interesting mixture of lectures (given by invited speakers of significant reputation), presentations of reviewed research papers, and student paper presentations. By tradition, it's location always switches between somewhere in Slowakia and the Czech Republique and always in winter. Unfortunately, this year winter did not really show up and thus, we are sitting here in Harrachow (a well known winter resort) without any snow. On the other hand, nice thing about this situation is that travelling this year has become much easier (because there is no snow even in the mountain areas).
This year, I am co-chairing the track 'emerging web technologies' as being one of the four SOFSEM tracks. By tradition, there is always a track 'foundations of computer science' besides of three changable tracks concering breaking topics of current interest , i.e. (in this year) 'multi-agent systems', 'emerging web technologies', and 'dependable software and systems'.
The first day on SOFSEM, after the opening note given by Jan van Leeuwen, in which he referred to the long tradition of SOFSEM and to Czech computer science history, starts with a full day of invited lectures covering all four topics.

  • Manfred Broy from TU Munich started with a presentation on 'Interaction and Realizability'. In interactive computation - in difference to sequential, atomic computation - input as well as output is not provided as a whole, but step by step while the computation continues. He pointed out that interactive behaviour can be modeled with Moore machines and introduced the term of 'realizability', which is a fundamental issue when asking whether a behaviour corresponds to a computation. 'Realizable functions' are defined as being abstractions of state machines (in a similar way as partial functions are abstractions of Turing machines) and can be used to extend the idea of computability to interactive computations.

  • Andrew Goldberg followed with a talk on 'Point-to-Point Shortest Path Algorithms with Preprocessing'. To run on even small devices while at the same time covering graphs with tens of millions of nodes (as, e.g., in roadmaps for navigation devices), off course efficient algorithms are required. The traditional way is to search a ball around the starting point (as e.g. in Dijkstra's algorithm) that can be speed up by biasing the search towards to intendet target point (as e.g. in A* search, if additional information is available that provides a lower-bound on the distance to the target) or by pruning the search graph (as e.g. in ALT algorithms that precompute distances to preselected landmarks, or using 'reaches').

  • Jerome Lang from IRIT (France) continued the afternoon session with a survey on 'Computational Issues in Group Decision Making', which combines 'social choice' (from economics) and AI (applications) into 'computational social choice' theory. In this new and very active discipline concepts as e.g. voting procedures, coalition formation, and fair division (from social choice), which is also important for multi-agent systems, are examined under the consideration of complexity analyses and algorithm design.

  • I realized that I will be the chairman of today's last session. Thus, the summary of Remco Veltkamp's (University of Utrecht, The Netherlands) talk on 'Multimedia Retrieval Algorithms' will come with a little delay....
    The presentation started with citing Marshal McLuhan's famous quote 'The medium is the message' smartly being connected to the basic definitions of multimedia retrieval. Difficult thing in multimedia retrieval is the proper understanding of the mechanisms of human perception and in connection to that the question of how to take care of it's peculiarity in information retrieval. E. g., the human visual system is famous for 'generic interpretations', i.e. sometimes we see things that are not really there, as already has been described by Wertheimer's Gestalttheorie back in 1923. Interesting fact, that some of these visual illusions do also exist for audio perception. For multimedia retrieval metrics have to be defined for computing similarities (as well as differences of multimedia objects) in an efficient way, while the algorithms dealing with multimedia retrieval have to be carefully designed according to the type of problem that is addressed (e.g., computing problem, optimization problem, decision problem, etc.). The presentation closed with a short demonstration of the music search engine Muugle that realizes the concept of 'query-by-humming'.

Saturday, January 13, 2007

...against all odds


On wednesday I attended a talk given by Michael Strube from EML Research on "World Knowledge induced from Wikipedia - A New Prospect of Knowledge-Based NLP ". He was showing how the (meanwhile famous) collaborative encyclopedia can be used for information retrieval purposes in a way similar to (more traditional) online dictionaries as e.g. WordNet and - though being not well structured - provides results of almost equal quality.
First thing was that for their work, Strube and his colleague regarded each Wikipedia page as being the representation of a concept (we already had some arguments about that as you might remember...). Next, they developed some metric for similarity of concepts w.r.t. to the concept hierarchy (where the wikipedia defined 'concepts' come into play). Since 2004, wikipedia features a user defined concept hierarchy. This hierarchy of concepts also can be regarded as being a folksonomy, simply because this is not a knowledge representation carefully designed by some designated domain expert, but by the wikipedia comunity in a collaborative way. Unfortunately, the wikipedia concept hierarchy suffers exactly from that fact. From my pont of view it seems problematic to compare the proposed similarity measure (based on wikipedia concept hierarchy) with other similarity measures (based on commonly shared expert ontologies). O.k., you might argue that indeed the wikipedia concept hierarchy IS commonly shared, because it has been developed by the wikipedia community...but is the knowledge represented in wikipedia really 'common'? Just remember the diversity and manifold of Star Wars characters or Star Trek episodes in wikipedia compared with, as e.g., the history of smaller Eropean countries. As for all ontologies always the view and the knowledge of the ontology designer has to be considered. The wikipedia concept hierarchy - although partly being really appropriate - reminds me somehow to this famous literary chinese dictonary entry defining the term 'animal' which is quoted by Jorge Luis Borges. Another problem lies in the fact that the different language versions of wikipedia have developed different concept hierarchies (sic!).

In the end, I was asking how this proposed information retrieval based on wikipedia could be improved by considering a 'Semantic Wikipedia', as e.g., the Semantic MediaWiki (given that those semantic wikipedias would contain sufficient data). Instead of answering my question, Michael Strube cited Peter Norwig's argument against the Semantic Web from last years AAI2006. Just to sum up: the semantic web will not become reality because of the inability of its users to provide correct semantic annotations. But hey...this guy (Strube) was talking about wikipedia. Doesn't this argument raise any associations? Just remember the time 5 or 10 years ago. Nobody (well almost nobody) would have believed that it will be possible to write an entire encyclopedia collaboratively on an open source basis - just because the web user's did not seem to be able to write 'correct' articles....

Sunday, January 07, 2007

Sam Bourne - Die Gerechten....


Etwas verspätet, aber bevor ich schon wieder das nächste Buch beendet habe, muss ich heute doch noch ein paar Worte über meine 'Feiertagslektüre', "Die Gerechten" von Sam Bourne verlieren:
Meine Erwartungen waren ja recht hoch gesteckt. Neugierig gemacht durch einen Beitrag der Kulturzeit wollte ich diesen als ungewöhnlichen Thriller angekündigten Roman unbedingt lesen. Will Monroe, ein junger Journalist der New York Times, deckt eine Spur ungewöhnlicher Morde auf, die erst auf dem zweiten Blick tatsächlich miteinander zusammenhängen. Er wird - zumindest bleibt er (und der Leser) zunächst in diesem Glauben - mit hineingezogen in eine jüdische-konservative (sic!) Weltverschwörung, deren Ziel in der Herbeiführung des Endes der Welt und im (damit erzwungenen) Erscheinen des langerwarteten Messias zu bestehen scheint. [ACHTUNG: SPOILER-WARNUNG] Fast bis zum Schluss wird man in diesem Glauben gelassen, aber 'natürlich' waren es dann doch irgendwelche sektiererischen, 'bibeltreuen' und erzkonservative Christen, die übrigens das gleiche Ziel verfolgen.[ENDE: SPOILER-WARNUNG]
Ehrlich gesagt, ich war enttäuscht. Nicht nur, dass der ganze Plott mehr als an den Haaren herbeigezogen scheint. Nein, eigentlich eher die mangelnde erzählerischen Qualitäten des Autors haben mich etwas verärgert. Die Personen werden stereotypisch (langweilig) und absolut vorhersehbar charakterisiert. Jeglicher Tiefgang - sei es der Vater-Sohn Konflikt der Hauptfigur, seine Beziehungsprobleme oder der Umgang mit seiner Ex-Freundin - erscheinen irgendwie vollkommen platt. Eigene Gedankengänge, die einem die Beweggründe der handelnden Personen näherbringen würden, fehlen fast völlig. Sicher, die Story enthält zahlreiche Cliffhanger und wird daher für eine Vielzahl der Leser spannende Lektüre bieten, aber der Handlungsfluss ist fast vollständig linear, einige Fragen bleiben ungeklärt, und die pseudo-wissenschaftlichen Herleitungen [ich sage nur: Kabbala und GPS...] verärgern den Leser eher als dass diese ihm ein Aha-Erlebnis bieten würden.

Fazit: Eine neue (alte) Verschwörungsgeschichte, die mit Endzeit-Phantasien, oberflächlich religiösen Vorurteilen und Kabbala-Techno-Babbel versucht, Boden gut zu machen, deren erzählerische Qualität meines Erachtens nach aber zu Wünschen übrig lässt...

P.S. Jedes neue Buch zum Thema Verschwörungstheorien muss sich gegen die zwei Meilensteine dieses Genres messen: Sear und Wilson's Illuminatus Trilogie (wenn schon, dann wenigstens absolut abgedreht....) oder man nimmt sich gleich den Großmeister Umberto Eco vor mit seinem Foucaultschen Pendel, in dem jegliche Verschwörungstheorien auf äußerst intelligente und lesenswerte Weise durchexerziert und ad absurdum geführt werden.