M. Volf and M. Studeny:
A graphical characterization of the largest chain graphs.
International Journal of Approximate Reasoning
20 (1999), pp. 209236.
 Abstract
 The paper presents a direct (explicit) graphical
characterization of the largest chain graph which serves as a
unique representative of the class of Markov equivalent chain graphs.
The characterization is a basis for an algorithm constructing for a
given chain graph the largest chain graph equivalent to it. The
algorithm was used to generate a catalogue of the largest chain graphs
with at most five vertices. Every entry of the catalogue contains the
largest chain graph of a class of Markov equivalent chain graphs and
an economical record of the induced independency model.
Note that the characterization theorem and the algorithm presented
in this paper differ substantially form a former characterization
theorem and algorithm described in the paper:
 M. Studeny:
A recovery algorithm for chain graphs.
International Journal of Approximate Reasoning
17 (1997), n. 23, pp. 265293.
 AMS classification 68T30, 62H05
 Keywords
 graphical models
 conditional independence
 chain graphs
 Markov equivalence
 the largest chain graph
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A
scanned pdf copy of the published paper (1188kB) is already openaccess available.
The paper also builds on the following works:
 M. Frydenberg: The chain graph Markov property.
Scandinavian Journal of Statistics
17 (1990), n. 3, pp. 333353.