Patent ID: 7912831

Claim:
A method comprising: accessing, by one or more computing devices, a set of web pages within a context, wherein: the set of web pages comprises a first subset of web pages with a first known characterization with respect to the context and a second subset of web pages with unknown characterization with respect to the context; and the set of web pages are directly or indirectly linked to each other via one or more hyperlinks; representing, by the one or more computing devices, the set of web pages using a graph comprising a set of nodes and a set of edges, wherein: each node represents a web page; and each edge links two nodes and represents a hyperlink that links two corresponding web pages represented by the two nodes; generating, by the one or more computing devices, a first probability distribution over the set of nodes of the graph using a first algorithm, wherein the first probability distribution indicates a first measure of closeness, as defined by the first algorithm, among the set of web pages, comprising: generating a first initial probability distribution over a first subset of nodes of the graph representing the first subset of web pages; and propagating the first initial probability distribution to other nodes of the graph in a direction same as the one or more hyperlinks using the first algorithm; generating, by the one or more computing devices, a second probability distribution over the set of nodes of the graph using the first algorithm, wherein the second probability distribution indicates a second measure of closeness, as defined by the first algorithm, among the set of web pages, comprising: generating a second initial probability distribution over a second subset of nodes of the graph representing the second subset of web pages; and propagating the second initial probability distribution to other nodes of the graph in a direction opposite to the one or more hyperlinks using the first algorithm; determining, by the one or more computing devices, a characterization with respect to the context for a web page from the second subset of web pages based on the first probability distribution and the second probability distribution; and outputting, by the one or more computing devices, an indication of the characterization of the web page from the second subset of web pages.