On the complexity of enumerating pseudo-intents
نویسندگان
چکیده
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...
متن کاملEnumerating Pseudo-Intents in a Partial Order
The enumeration of all the pseudo-intents of a formal context is usually based on a linear order on attribute sets, the lectic order. We propose an algorithm that uses the lattice structure of the set of intents and pseudo-intents to compute the Duquenne-Guigues basis. We argue that this method allows for efficient optimizations that reduce the required number of logical closures. We then show ...
متن کاملHardness of Enumerating Pseudo-intents in the Lectic Order
We investigate the complexity of enumerating pseudo-intents in the lectic order. We look at the following decision problem: Given a formal context and a set of n pseudo-intents determine whether they are the lectically first n pseudo-intents. We show that this problem is coNPhard. We thereby show that there cannot be an algorithm with a good theoretical complexity for enumerating pseudo-intents...
متن کاملTowards the Complexity of Recognizing Pseudo-intents
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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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2011
ISSN: 0166-218X
DOI: 10.1016/j.dam.2010.12.004