Tunable and Growing Network Generation Model with Community Structures

Recent years have seen a growing interest in the modeling and simulation of social networks to understand several social phenomena. Two important classes of networks, small world and scale free networks have gained a lot of research interest. Another important characteristic of social networks is the presence of community structures. Many social processes such as information diffusion and disease epidemics depend on the presence of community structures making it an important property for network generation models to be incorporated. In this paper, we present a tunable and growing network generation model with small world and scale free properties as well as the presence of community structures. The major contribution of this model is that the communities thus created satisfy three important structural properties: connectivity within each community follows power-law, communities have high clustering coefficient and hierarchical community structures are present in the networks generated using the proposed model. Furthermore, the model is highly robust and capable of producing networks with a number of different topological characteristics varying clustering coefficient and inter-cluster edges. Our simulation results show that the model produces small world and scale free networks along with the presence of communities depicting real world societies and social networks.Comment: Social Computing and Its Applications, SCA 13, Karlsruhe : Germany (2013

RNA-SequenLens for Visualizing RNA Secondary Structures

Runner up of the Design ContestInternational audienceIn this paper, we present RNA-SequenLens to facilitate the visualization and comparison of RNA secondary structures.With RNA-SequenLens, all possible base pairings of a RNA sequence can be visualized at the desired probability threshold. Different RNA secondary structures can be easily compared. The interactive demo is available at https://youtu.be/C6EDC8LZJX

Node Overlap Removal Algorithms: A Comparative Study

Appears in the Proceedings of the 27th International Symposium on Graph Drawing and Network Visualization (GD 2019)Many algorithms have been designed to remove node overlapping, and many quality criteria and associated metrics have been proposed to evaluate those algorithms. Unfortunately, a complete comparison of the algorithms based on some metrics that evaluate the quality has never been provided and it is thus difficult for a visualization designer to select the algorithm that best suits his needs. In this paper, we review 21 metrics available in the literature, classify them according to the quality criteria they try to capture, and select a representative one for each class. Based on the selected metrics, we compare 8 node overlap removal algorithms. Our experiment involves 854 synthetic and real-world graphs

SequencesViewer : comment rendre accessible des motifs séquentiels de gènes trop nombreux ?

National audienceLes techniques d'extraction de connaissances ppliquées aux gros volumes de données, issus de l'analyse de puces ADN, permettent de découvrir des connaissances jusqu'alors inconnues. Or, ces techniques produisent de très nombreux résultats, difficilement exploitables par les experts. Nous proposons un outil dédié à l'accompagnement de ces experts dans l'appropriation et l'exploitation de ces résultats. Cet outil est basé sur trois techniques de visualisation (nuages, systèmes solaire et treemap) qui permettent aux biologistes d'appréhender de grandes quantités de motifs séquentiels (séquences ordonnées de gènes)

Discovering Novelty in Gene Data : From Sequential Patterns to Visualization

International audienceData mining techniques allow users to discover novelty in huge amounts of data. Frequent pattern methods have proved to be efficient, but the extracted patterns are often too numerous and thus difficult to analyse by end-users. In this paper, we focus on sequential pattern mining and propose a new visualization system, which aims at helping end-users to analyse extracted nowledge and to highlight the novelty according to referenced biological document databases. Our system is based on two visualization techniques: Clouds and solar systems. We show that these techniques are very helpful for identifying associations and hierarchical relationships between patterns among related documents. Sequential patterns extracted from gene data using our system were successfully evaluated by two biology laboratories working on Alzheimers disease and cancer

Generating Artificial Social Networks with Small World and Scale Free Properties

Recent interest in complex networks has catalyzed the development of numerous models to help artificially generate and understand these networks. Watts and Strogatz presented a model (Watts Strogatz 1998) to explain how the two properties of small world networks, high clustering coefficient and low average path length appear in networks. (Barabasi and Albert 1999) gave a model to explain how networks with power-law degree distribution arise in networks. From these two ground breaking results, many researchers have introduced different models to explain the appearance of networks with small world and scale free properties in the real world. In this paper, we focus on social networks and comparatively study the structure of real world and artificially generated networks. The differences and similarities of different models are highlighted and their shortcomings are identified. Further more, we present a new model which produces networks with both small world and scale free properties which are structurally more similar to real world social networks

Revealing Hidden Community Structures and Identifying Bridges in Complex Networks: An Application to Analyzing Contents of Web Pages for Browsing

International audienceThe emergence of scale free and small world properties in real world complex networks has stimulated lots of activity in the field of network analysis. An example of such a network comes from the field of Content Analysis (CA) and Text Mining where the goal is to analyze the contents of a set of web pages. The Network can be represented by the words appearing in the web pages as nodes and the edges representing a relation between two words if they appear in a document together. In this paper we present a CA system that helps users analyze these networks representing the textual contents of a set of web pages visually. Major contributions include a methodology to cluster complex networks based on duplication of nodes and identification of bridges i.e. words that might be of user interest but have a low frequency in the document corpus. We have tested this system with a number of data sets and users have found it very useful for the exploration of data. One of the case studies is presented in detail which is based on browsing a collection of web pages on Wikipedia (http://en.wikipedia.org/wiki/Main_Page)

Interactive Visualization and Navigation of Web Search Results Revealing Community Structures and Bridges

International audienceWith the information overload on the Internet, organization and visualization of web search results so as to facilitate faster access to information is a necessity. The classical methods present search results as an ordered list of web pages ranked in terms of relevance to the searched topic. Users thus have to scan text snippets or navigate through various pages before finding the required information. In this paper we present an interactive visualization system for content analysis of web search results. The system combines a number of algorithms to present a novel layout methodology which helps users to analyze and navigate through a collection of web pages. We have tested this system with a number of data sets and have found it very useful for the exploration of data. Different case studies are presented based on searching different topics on Wikipedia through Exalead's search engine