PASCAL - Pattern Analysis, Statistical Modelling and Computational Learning

First-order definable problems for posets and reflexive graphs
Victor Dalmau, A Krokhin and B. Larose
In: LICS 04, 14-17 July 2004, Turku, Finland.


A retraction from a structure P to its substructure Q is a homomorphism from P onto Q that is the identity on Q. We present an algebraic condition which completely characterizes all posets and all reflexive graphs Q with the following poperty: the class of all posets or reflexive graphs, respectively, that admits a retraction onto Q is first-order definable.

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EPrint Type:Conference or Workshop Item (Paper)
Project Keyword:Project Keyword UNSPECIFIED
Subjects:Theory & Algorithms
ID Code:706
Deposited By:Victor Dalmau
Deposited On:29 November 2005