405,762 research outputs found
Tree, web and average web value for cycle-free directed graph games
On the class of cycle-free directed graph games with transferable utility solution concepts, called web values, are introduced axiomatically, each one with respect to some specific choice of a management team of the graph. We provide their explicit formula representation and simple recursive algorithms to calculate them. Additionally the efficiency and stability of web values are studied. Web values may be considered as natural extensions of the tree and sink values as has been defined correspondingly for rooted and sink forest graph games. In case the management team consists of all sources (sinks) in the graph a kind of tree (sink) value is obtained. In general, at a web value each player receives the worth of this player together with his subordinates minus the total worths of these subordinates. It implies that every coalition of players consisting of a player with all his subordinates receives precisely its worth. We also define the average web value as the average of web values over all management teams in the graph. As application the water distribution problem of a river with multiple sources, a delta and possibly islands is considered
Bigraphical Logics for XML
Bigraphs have been recently proposed as a meta-model for global computing resources; they are built orthogonally on two structures: a hierarchical ‘place’ graph for locations and a ‘link’ (hyper-)graph for connections. XML is now the standard meta-language for the data exchange and storage on the web. In this paper we address the similarities between bigraphs and XML and we propose bigraphs as a rich model for XML (and XML contexts). Building on this idea we proceed by investigating how the recently proposed logic of BiLog can be instantiated to describe, query and reason about web data (and web contexts)
Analysis of the Web Graph Aggregated by Host and Pay-Level Domain
In this paper the web is analyzed as a graph aggregated by host and pay-level
domain (PLD). The web graph datasets, publicly available, have been released by
the Common Crawl Foundation and are based on a web crawl performed during the
period May-June-July 2017. The host graph has 1.3 billion nodes and
5.3 billion arcs. The PLD graph has 91 million nodes and 1.1
billion arcs. We study the distributions of degree and sizes of strongly/weakly
connected components (SCC/WCC) focusing on power laws detection using
statistical methods. The statistical plausibility of the power law model is
compared with that of several alternative distributions. While there is no
evidence of power law tails on host level, they emerge on PLD aggregation for
indegree, SCC and WCC size distributions. Finally, we analyze distance-related
features by studying the cumulative distributions of the shortest path lengths,
and give an estimation of the diameters of the graphs
SWING: A system for visualizing web graphs
A Web graph refers to the graph that is used to represent relationships between Web pages in cyberspace, where a node represents a URL and an edge indicates a link between two URLs. A Web graph is a very huge graph as growing with cyberspace. This paper presents a pipeline for extracting web information from cyberspace to a web graph and layout techniques for making the web graph more readable. As the size of computer screen is limited, only a small part of the Web graph can be displayed. Several layout techniques should be adapted and combined effectively for web graph visualization. The visualization process incorporates graph drawing algorithms, layout adjustment methods, as well as filtering and clustering methods in order to decide which part of the Web graph should be displayed and how to display it based on the user's focus in navigation
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