Prof Jürg Kohlas


  • Professor emeritus of Theoretical Computer Science

Research Interests

Algebraic Theory of Information

Information is related to questions, it must be focused on the questions of interest, and it comes often in different pieces, or from different sources and must aggregated. This can be captured in two-sorted algebras, linking elements representing pieces of information and elements representing distinct questions. In this research project, these algebras are studied based on different, but related axiomatic bases. These algebras allow for generic distributed local computation schemes. Different computational architectures are developed and implemented. Further representations of information based either on universal logic systems or on general relational systems are studied. Finally, uncertain information is modeled by random variables taking values in information algebras.

most recent research:

Algebras of Information. A New and Extended Axiomatic Foundation

Probabilistic Argumentation

Often information depends on uncertain assumptions. Hypotheses may then be deduced or proved assuming certain of these assumptions. By considering the likelihood or probability of the assumptions involved, the reliability with which the hypotheses can be deduced or proved can be computed. This defines degrees of support for the hypotheses. These degrees form belief functions in the sense of Dempster-Shafer theory of evidence. These probabilistic argumentation systems link logic and probability for inference in a very natural way going back to the founder of stochastics, J. Bernoulli. Computational architectures for probabilistic argumentation systems have been implemented in the framework of propositional logic. Further, in the abstract setting of information algebras they are induced by random variables with value in information algebras. In this direction the project is pursued under the first heading.

Other Work

History of Computing

Other Activities

Further Activities

Recent Publications

Up-to-date: 
Books:

Theory of Hints      Information Theory      

Coeditor of:

 Software, Computing, Networks

Recent Papers:
Further Papers:

See my publication list here.

New: Computer Science in School:

The German version is out of print. It is however available as e-book, see here

Alternatively it can be downloaded here

Press Articles on Computer Science in School:

La Liberté: L'informatique en branche principale

La Liberté: Urgent: Cherche informaticiens

Sonntagszeitung: Kosten sparen

La Liberté: La science informatique pourrait devenir une branche principale

L'HEBDO: Sus à l'analphabétisme informatique

Freiburger Nachrichten: Um die neue Welt besser verstehen zu können
 

 

 

Contact

Kohlas Jürg
Department of Informatics
Boulevard de Pérolles 90
1700 FRIBOURG
(Switzerland)
office : PER 2, C409
phone : +41 26 300 8338
e-mail : juerg.kohlas@unifr.ch