The Wikipedia Game
http://www.news.com.au/technology/the-wikipedia-article-philosophy-game-in-numbers/story-e6frfro0-1226119845491
Everyone has played the Wikipedia game before –picking a random start page with a random end page in mind, to see who can get there in the least amount of time/clicks –but the question is, is it really possible to always get from point X to point Y? Are all pages on Wikipedia part of a strongly connected component?
An article posted a few months ago sheds some light on this game from the original game called the philosophy game –where one picks a random start page and tries to get to the end page philosophy. As the article states, “Someone on Reddit discovered it. XKRD joked about it. Wikipedia made a page for it. But now, someone’s actually run the numbers on it.” The article claims that over 3.5 million pages were found to eventually lead back to philosophy, while about 100 thousand cannot lead back to philosophy at all. These “dead links” are half never ending loop and half just a dead end. Also it is stated that the common number of clicks or links to get to the philosophy page is 23; that sounds like a pretty large strongly connected component.
It seems that Wikipedia is a directed graph that is comprised of one giant strongly connected component, with maybe a few smaller ones here or there that cannot connect back along a path to the largest one, and perhaps some components that are very small, like a never ending loop between two or three related pages. Who would have thought that 100,000 pages could possibly not be a part of the larger component? I have always assumed that when I played the Wikipedia game, that I could always get from my random subject X to my random subject Y. But I guess not. Even though Wikipedia does have a major strongly connected component, you and your friends may embark on a Wikipedia game that is never to be finished.