Depth-first Search for Pseudo-intents through Minimal Transversals
نویسنده
چکیده
The enumeration of pseudo-intents is a long-standing problem in which the order plays a major role. In this paper, we present new algorithms that enumerate pseudo-intents in orders that do not necessarily respect the inclusion relation. We show that, confirming established results, this enumeration is equivalent to computing minimal transversals in hypergraphs a bounded number of times.
منابع مشابه
On the complexity of enumerating pseudo-intents
We investigate whether the pseudo-intents of a given formal context can efficiently be enumerated. We show that they cannot be enumerated in a specified lexicographic order with polynomial delay unless p = np. Furthermore we show that if the restriction on the order of enumeration is removed, then the problem becomes at least as hard as enumerating minimal transversals of a given hypergraph. We...
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Pseudo-intents play a key rôle in Formal Concept Analysis. They are the premises of the implications in the Duquenne-Guigues Base, which is a minimum cardinality base for the set of implications that hold in a formal context. It has been shown that checking whether a set is a pseudo-intent is in conp. However, it is still open whether this problem is conp-hard, or it is solvable in polynomial t...
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The enumeration of pseudo-intents is a long-standing problem in which the order plays a major role. In this paper, we present new algorithms that enumerate pseudo-intents in orders that do not necessarily respect the inclusion relation. We show that, confirming established results, this enumeration is equivalent to computing minimal transversals in hypergraphs a bounded number of times.
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تاریخ انتشار 2015