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Deterministic Automata on Unranked Trees
 In Proceedings of the 15th International Symposium on Fundamentals of Computation Theory (FCT), LNCS
, 2005
"... Abstract. We investigate bottomup and topdown deterministic automata on unranked trees. We show that for an appropriate denition of bottomup deterministic automata it is possible to minimize the number of states eciently and to obtain a unique canonical representative of the accepted tree langua ..."
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Cited by 30 (1 self)
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language. For topdown deterministic automata it is well known that they are less expressive than the nondeterministic ones. By generalizing a corresponding proof from the theory of ranked tree automata we show that it is decidable whether a given regular language of unranked trees can be recognized by a
LOGICS FOR UNRANKED TREES: AN OVERVIEW
 CONSIDERED FOR PUBLICATION IN LOGICAL METHODS IN COMPUTER SCIENCE
, 2006
"... Labeled unranked trees are used as a model of XML documents, and logical languages for them have been studied actively over the past several years. Such logics have different purposes: some are better suited for extracting data, some for expressing navigational properties, and some make it easy to ..."
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Cited by 40 (7 self)
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Labeled unranked trees are used as a model of XML documents, and logical languages for them have been studied actively over the past several years. Such logics have different purposes: some are better suited for extracting data, some for expressing navigational properties, and some make it easy
An Efficient Boosting Algorithm for Combining Preferences
, 1999
"... The problem of combining preferences arises in several applications, such as combining the results of different search engines. This work describes an efficient algorithm for combining multiple preferences. We first give a formal framework for the problem. We then describe and analyze a new boosting ..."
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Cited by 707 (18 self)
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boosting algorithm for combining preferences called RankBoost. We also describe an efficient implementation of the algorithm for certain natural cases. We discuss two experiments we carried out to assess the performance of RankBoost. In the first experiment, we used the algorithm to combine different WWW
Ranking and unranking permutations in linear time
 INFORMATION PROCESSING LETTERS 79 (2001) 281–284
, 2001
"... A ranking function for the permutations on n symbols assigns a unique integer in the range [0,n!−1] to each of the n! permutations. The corresponding unranking function is the inverse: given an integer between 0 and n!−1, the value of the function is the permutation having this rank. We present simp ..."
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Cited by 36 (0 self)
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A ranking function for the permutations on n symbols assigns a unique integer in the range [0,n!−1] to each of the n! permutations. The corresponding unranking function is the inverse: given an integer between 0 and n!−1, the value of the function is the permutation having this rank. We present
Ranking and unranking trees with given degree sequences
"... In this paper, we provide algorithms to rank and unrank certain degreerestricted classes of Cayley trees. Specifically, we consider classes of trees that have a given degree sequence or a given multiset of degrees. Using special properties of a bijection due to Eğecioğlu and Remmel [3], we show t ..."
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In this paper, we provide algorithms to rank and unrank certain degreerestricted classes of Cayley trees. Specifically, we consider classes of trees that have a given degree sequence or a given multiset of degrees. Using special properties of a bijection due to Eğecioğlu and Remmel [3], we show
Querying unranked trees with stepwise tree automata
 Intenational Conf. on Rewriting Techniques and Applications
, 2004
"... Abstract. The problem of selecting nodes in unranked trees is the most basic querying problem for XML. We propose stepwise tree automata for querying unranked trees. Stepwise tree automata can express the same monadic queries as monadic Datalog and monadic secondorder logic. We prove this result by ..."
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Cited by 43 (20 self)
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Abstract. The problem of selecting nodes in unranked trees is the most basic querying problem for XML. We propose stepwise tree automata for querying unranked trees. Stepwise tree automata can express the same monadic queries as monadic Datalog and monadic secondorder logic. We prove this result
Ranking and unranking left Szilard languages
 ISO/IEC JTC1/SC29/WGLL/N2467, ATLANTIC CITY
, 1997
"... We give efficient ranking and unranking algorithms for left Szilard languages of contextfree grammars. If O(n2) time and space preprocessing is allowed then each ranking operation is possible in linear time. Unranking takes time O(n log n). These algorithms imply similar algorithms for contextfr ..."
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Cited by 2 (1 self)
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We give efficient ranking and unranking algorithms for left Szilard languages of contextfree grammars. If O(n2) time and space preprocessing is allowed then each ranking operation is possible in linear time. Unranking takes time O(n log n). These algorithms imply similar algorithms for context
Temporal logics over unranked trees
 In LICS’05
"... We consider unranked trees, that have become an active subject of study recently due to XML applications, and characterize commonly used fragments of firstorder (FO) and monadic secondorder logic (MSO) for them via various temporal logics. We look at both unordered trees and ordered trees (in which ..."
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Cited by 27 (2 self)
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We consider unranked trees, that have become an active subject of study recently due to XML applications, and characterize commonly used fragments of firstorder (FO) and monadic secondorder logic (MSO) for them via various temporal logics. We look at both unordered trees and ordered trees (in
REWRITING SYSTEMS OVER UNRANKED TREES
, 2006
"... Finite graphs constitute an important tool in various fields of computer science. In order to transfer the theory of finite graphs at least partially to infinite systems, a finite representation of infinite systems is needed. Rewriting systems form a practical model for the finite representation of ..."
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Cited by 1 (0 self)
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of infinite graphs. Among attractive subclasses of rewriting systems is the class of ground tree rewriting systems over ranked trees, which is known to have good algorithmic properties. We investigate these algorithmic properties for two kinds of rewriting systems over unranked trees. For the first introduced
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