C+5.1+-+The+Web+as+a+directed+Graph


 * __How can the web be presented as a directed graph? __**

__**Web Graph**__

 * **Theory: everything linked somehow**
 * a web graph is a directed graph
 * it is an incomplete graph
 * shows the structure of the web
 * **nodes** = webpages
 * **edges** = hyperlinks leading to more info

__**Subgraphs**__

 * **set of pages linked to one specific topic**
 * specific group shown not all sites are displayed
 * a subgraph is a graph within a web graph

__**Structure of the web**__

 * **depends on the behaviour of users**
 * our use/behaviour[[image:Screen Shot 2014-09-18 at 20.33.25.png width="343" height="200" align="right" caption="Bow Tie Web Graph"]]
 * move to specific areas physically changes the shape
 * e.g. through reposting/linking as new edges are created

__Bow tie **Theory**__

 * **shape of the graph believed to be a bow tie**
 * **SCC:** strongly connected core
 * **IN:** websites connected to the SCC
 * **OUT:** links leading from the SCC to websites, but not back

__MATH LINK: Graph Theory__

 * Graph Theory:
 * the study of graphs, which model relations between objects
 * a graph uses **nodes** ( vertices ) and **edges**, which are the connecting lines
 * **undirected**: __no connection__ between nodes through edges
 * **directed**: connection between nodes through edges
 * used for many subjects
 * e.g. biological information
 * __**Computer Science relation:**__
 * ** deriving algorithms **
 * diagram
 * e.g. circuits, web graph
 * modelling networks
 * operation research
 * solving OR problems
 * **USE in terms of web graphs:**
 * **marketing**
 * **data mining**
 * **analysing** **organisation**
 * **networking**
 * **clustering**
 * **prediction**
 * **connections**

Created By: Lucie Magister Last update: 18/09/2014

Sources:
 * "Graph Theory." Wikipedia. Wikimedia Foundation, 14 Sept. 2014. Web. 18 Sept. 2014. .
 * Magister, Lucie. Class Notes. 11 Sep. 2014.
 * S.g. Shrinivas Et. Al. / International Journal Of Engineering Science And Technology, and Vol. 2(9) 2010 4610-4621. "APPLICATIONS OF GRAPH THEORY IN COMPUTER SCIENCE AN OVERVIEW."International Journal of Engineering, Science and Technology (n.d.): n. pag. Xavier University Computer Science. Web. 18 Sept. 2014. .