Chapter 8, Problem 20E

Wobble, a start-up company, is developing a search engine for the Web. Given a particular search word, say Angelface (the name of a rock band), Wobbles strategy is to find all the Web sites containing the term Angelface, and then look at Web sites to which those Web sites link, to obtain a ranked list of search results. In other words, if there are lots of links pointing to Web site X from Web sites that mention Angelface, then it is likely that X contains lots of useful information about Angelface. In the digraph shown in Fig. 8-31, the vertices represent Web pages that contain the word Angelface and the arcs represent hyperlinks from one Web site to another.

a. Which Web sites would show up first, second, and third in the search results? Explain your answer.

b. One of the vertices of the digraph is the official Angelface Web site. Which do you think it is? Explain your answer.

Figure 8-31