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Fixedparameter tractability and data reduction for Multicut in Trees
 Networks
, 2005
"... We study an NPcomplete (and MaxSNPhard) communication problem on tree networks, the socalled Multicut in Trees: given an undirected tree and some pairs of nodes of the tree, find out whether there is a set of at most k tree edges whose removal separates all given pairs of nodes. Multicut has been ..."
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Cited by 14 (4 self)
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been intensively studied for trees as well as for general graphs mainly from the viewpoint of polynomialtime approximation algorithms. By way of contrast, we provide a simple fixedparameter algorithm for Multicut in Trees showing
Drawing (complete) binary tanglegrams: Hardness, approximation, fixedparameter tractability
, 2008
"... A binary tanglegram is a pair 〈S, T 〉 of binary trees whose leaf sets are in onetoone correspondence; matching leaves are connected by intertree edges. For applications, for example in phylogenetics, it is essential that both trees are drawn without edge crossings and that the intertree edges ..."
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Cited by 9 (2 self)
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binary trees. We show that the problem is hard even if both trees are complete binary trees. For this case we give an O(n³)time 2approximation and a new and simple fixedparameter algorithm. We show that the maximization version of the dual problem for general binary trees can be reduced to a version
FixedParameter Algorithms In Phylogenetics
, 2007
"... We survey the use of fixedparameter algorithms in the field of phylogenetics, which is the study of evolutionary relationships. The central problem in phylogenetics is the reconstruction of the evolutionary history of biological species, but its methods also apply to linguistics, philology or archi ..."
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Cited by 11 (1 self)
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We survey the use of fixedparameter algorithms in the field of phylogenetics, which is the study of evolutionary relationships. The central problem in phylogenetics is the reconstruction of the evolutionary history of biological species, but its methods also apply to linguistics, philology
On efficient fixedparameter algorithms for . . .
, 2000
"... We investigate the fixedparameter complexity of Weighted Vertex Cover. Given a graph G = (V, E), a weight function ω: V → R +, and k ∈ R +, Weighted Vertex Cover (WVC for short) asks for a vertex subset C ⊆ V of total weight at most k such that every edge of G has at least one endpoint in C. WVC an ..."
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We investigate the fixedparameter complexity of Weighted Vertex Cover. Given a graph G = (V, E), a weight function ω: V → R +, and k ∈ R +, Weighted Vertex Cover (WVC for short) asks for a vertex subset C ⊆ V of total weight at most k such that every edge of G has at least one endpoint in C. WVC
FixedParameter Algorithms for . . .
 ROCEEDINGS OF THE 30TH INTERNATIONAL COLLOQUIUM ON AUTOMATA, LANGUAGES AND PROGRAMMING (ICALP’03)
, 2003
"... ..."
Fixedparameter algorithms for . . .
, 2003
"... FestparameterAlgorithmen bieten einen konstruktiven Ansatz zur Losung von kombinatorisch schwierigen, in der Regel NPharten Problemen, der zwei Ziele berucksichtigt: innerhalb von beweisbaren Laufzeitschranken werden optimale Ergebnisse berechnet. Die entscheidende Idee ist dabei, einen oder mehr ..."
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Cited by 1 (0 self)
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mehrere Aspekte der Problemeingabe als Parameter der Problems aufzufassen und die kombinatorische Explosion der algorithmischen Schwierigkeit auf diese Parameter zu beschranken, so dass die Laufzeitkosten polynomiell in Bezug auf den nichtparametrisierten Teil der Eingabe sind. Gibt es einen
Fixedparameter tractability and logic
 In preparation
, 1999
"... We exhibit a close connection between parameterized complexity theory and logic. Our approach is that of descriptive complexity theory. We study the definability of parameterized problems and try to obtain information about the parameterized complexity of the problems through the syntactical structu ..."
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Cited by 3 (2 self)
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structure of the defining sentences. On the one hand, we use this approach to prove that certain problems are fixedparameter tractable because they can be defined by syntactically simple formulas. On the other hand, we characterize classes of intractable problems by syntactical means. 1
A Simple, Fast, and Accurate Algorithm to Estimate Large Phylogenies by Maximum Likelihood
, 2003
"... The increase in the number of large data sets and the complexity of current probabilistic sequence evolution models necessitates fast and reliable phylogeny reconstruction methods. We describe a new approach, based on the maximumlikelihood principle, which clearly satisfies these requirements. The ..."
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Cited by 2110 (27 self)
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. The core of this method is a simple hillclimbing algorithm that adjusts tree topology and branch lengths simultaneously. This algorithm starts from an initial tree built by a fast distancebased method and modifies this tree to improve its likelihood at each iteration. Due to this simultaneous adjustment
Results 1  10
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1,976,682