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36
Finding Interesting Rules from Large Sets of Discovered Association Rules
, 1994
"... Association rules, introduced by Agrawal, Imielinski, and Swami, are rules of the form "for 90 % of the rows of the relation, if the row has value 1 in the columns in set W , then it has 1 also in column B". Efficient methods exist for discovering association rules from large collections of data. Th ..."
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Cited by 202 (9 self)
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Association rules, introduced by Agrawal, Imielinski, and Swami, are rules of the form "for 90 % of the rows of the relation, if the row has value 1 in the columns in set W , then it has 1 also in column B". Efficient methods exist for discovering association rules from large collections of data. The number of discovered rules can, however, be so large that browsing the rule set and finding interesting rules from it can be quite difficult for the user. We show how a simple formalism of rule templates makes it possible to easily describe the structure of interesting rules. We also give examples of visualization of rules, and show how a visualization tool interfaces with rule templates. 1 Introduction Data mining (knowledge discovery in databases) is a field of increasing interest combining databases, artificial intelligence, and machine learning. The purpose of data mining is to facilitate understanding large amounts of data by discovering interesting regularities or exceptions (see e...
SpaceTree: Supporting Exploration in Large Node Link Tree, Design Evolution and Empirical Evaluation
, 2002
"... We present a novel tree browser that builds on the conventional node link tree diagrams. It adds dynamic rescaling of branches of the tree to best fit the available screen space, optimized camera movement, and the use of preview icons summarizing the topology of the branches that cannot be expanded. ..."
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Cited by 107 (16 self)
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We present a novel tree browser that builds on the conventional node link tree diagrams. It adds dynamic rescaling of branches of the tree to best fit the available screen space, optimized camera movement, and the use of preview icons summarizing the topology of the branches that cannot be expanded. In addition, it includes integrated search and filter functions. This paper reflects on the evolution of the design and highlights the principles that emerged from it. A controlled experiment showed benefits for navigation to already previously visited nodes and estimation of overall tree topology.
TreePlus: Interactive Exploration of Networks with Enhanced Tree Layouts
 IEEE Transactions on Visualization and Computer Graphics
, 2006
"... Abstract—Despite extensive research, it is still difficult to produce effective interactive layouts for large graphs. Dense layout and occlusion make food webs, ontologies, and social networks difficult to understand and interact with. We propose a new interactive Visual Analytics component called T ..."
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Cited by 31 (4 self)
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Abstract—Despite extensive research, it is still difficult to produce effective interactive layouts for large graphs. Dense layout and occlusion make food webs, ontologies, and social networks difficult to understand and interact with. We propose a new interactive Visual Analytics component called TreePlus that is based on a treestyle layout. TreePlus reveals the missing graph structure with visualization and interaction while maintaining good readability. To support exploration of the local structure of the graph and gathering of information from the extensive reading of labels, we use a guiding metaphor of “Plant a seed and watch it grow. ” It allows users to start with a node and expand the graph as needed, which complements the classic overview techniques than can be effective at but often limited to revealing clusters. We describe our design goals, describe the interface, and report on a controlled user study with 28 participants comparing TreePlus with a traditional graph interface for six tasks. In general, the advantage of TreePlus over the traditional interface increased as the density of the displayed data increased. Participants also reported higher levels of confidence in their answers with TreePlus and most of them preferred TreePlus.
Circular Drawings of Rooted Trees
 IN REPORTS OF THE CENTRE FOR MATHEMATICS AND COMPUTER SCIENCES
, 1998
"... We describe an algorithm producing circular layouts for trees, that is drawings, where subtrees of a node lie within circles, and these circles are themselves placed on the circumference of a circle. The complexity and methodology of our algorithm compares to Reingold and Tilford's algorithm for ..."
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Cited by 19 (1 self)
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We describe an algorithm producing circular layouts for trees, that is drawings, where subtrees of a node lie within circles, and these circles are themselves placed on the circumference of a circle. The complexity and methodology of our algorithm compares to Reingold and Tilford's algorithm for trees [11]. Moreover, the algorithm naturally admits distortion transformations of the layout. This, added to its low complexity, makes it very well suited to be used in an interactive environment.
Improving Walker's Algorithm to Run in Linear Time
, 2002
"... The algorithm of Walker [3] is widely used for drawing trees of unbounded degree, and it is widely assumed to run in linear time, as the author claims in his article. But the presented algorithm obviously needs quadratic runtime. We explain the reasons for that and present arevised algorithm that cr ..."
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Cited by 17 (0 self)
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The algorithm of Walker [3] is widely used for drawing trees of unbounded degree, and it is widely assumed to run in linear time, as the author claims in his article. But the presented algorithm obviously needs quadratic runtime. We explain the reasons for that and present arevised algorithm that creates the same layouts in linear time.
An Experimental Comparison of Three Graph Drawing Algorithms (Extended Abstract)
, 1995
"... In this paper we present an extensive experimental study... ..."
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Cited by 15 (5 self)
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In this paper we present an extensive experimental study...
Comparing and Evaluating Layout Algorithms within GraphEd
 J. Visual Languages and Computing
, 1995
"... This paper is organized as follows. In section 2, we present an overview on the GraphEd system and the implemented graph drawing algorithms. Section 3 explains our evaluation experiments, and Section 4 shows our results. In Section 5 we give a subjective ranking of layout criteria. 2 GraphEd ..."
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Cited by 15 (2 self)
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This paper is organized as follows. In section 2, we present an overview on the GraphEd system and the implemented graph drawing algorithms. Section 3 explains our evaluation experiments, and Section 4 shows our results. In Section 5 we give a subjective ranking of layout criteria. 2 GraphEd
AGDLibrary: A Library of Algorithms for Graph Drawing
, 1997
"... A graph drawing algorithm produces a layout of a graph in two or threedimensional space that should be readable and easy to understand. Since the aesthetic criteria differ from one application area to another, it is unlikely that a definition of the "optimal drawing" of a graph in a strict math ..."
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Cited by 13 (5 self)
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A graph drawing algorithm produces a layout of a graph in two or threedimensional space that should be readable and easy to understand. Since the aesthetic criteria differ from one application area to another, it is unlikely that a definition of the "optimal drawing" of a graph in a strict mathematical sense exists. A large number of graph drawing algorithms taking different aesthetic criteria into account have already been proposed. In this paper we describe the design and implementation of the AGDLibrary, a library of Algorithms for Graph Drawing. The library offers a broad range of existing algorithms for twodimensional graph drawing and tools for implementing new algorithms. The library is written in C++ using the LEDA platform for combinatorial and geometric computing ([16, 17]). The algorithms are implemented independently of the underlying visualization or graphics system by using a generic layout interface. Most graph drawing algorithms place a set of restriction...
Visualizing graphs  a generalized view
 In Proceedings of the conference on Information Visualization (IV’06
, 2006
"... The visualization of graphs has proven to be very useful for exploring structures in different application domains. However, in certain fields of computer science, graph visualization is understood and focused quite differently. While ”graph drawing ” focuses on optimized layouts for nodelinkrepres ..."
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Cited by 12 (2 self)
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The visualization of graphs has proven to be very useful for exploring structures in different application domains. However, in certain fields of computer science, graph visualization is understood and focused quite differently. While ”graph drawing ” focuses on optimized layouts for nodelinkrepresentations of networks, ”information visualization” prefers to work on hierarchies focusing on very large structures, different views and interactivity. This paper gives a systematic view of the problem of graph visualization by combining both approaches. We will introduce a general view of different visualization methods as well as describe occurring problems and discuss basic constraints. These will be used to propose a visualization framework for graphs, whose development motivated this paper.
Latour  a Tree Visualisation System
 In Proceedings of the Symposium on Graph Drawing ’99
, 1999
"... This paper presents some of the most important features of a tree visualisation system called Latour, developed for the purposes of information visualisation. This system includes a number of interesting and unique characteristics, for example the provision for visual cues based on complexity metric ..."
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Cited by 11 (0 self)
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This paper presents some of the most important features of a tree visualisation system called Latour, developed for the purposes of information visualisation. This system includes a number of interesting and unique characteristics, for example the provision for visual cues based on complexity metrics on graphs, which represent general principles that, in our view, graph based information visualisation systems should generally offer.