Nonlinear Algorithms for Static-Rank Computation
- Bin Lu ,
- Shuming Shi ,
- Yunxiao Ma ,
- Ji-Rong Wen
MSR-TR-2009-55 |
Mainstream link-based static-rank algorithms (e.g. PageRank and its variants) express the importance of a page as the linear combination of its in-links and compute page importance scores by solving a linear system in an iterative way. Such linear algorithms, however, may give apparently unreasonable static-rank results for some link structures. In this paper, we examine the static-rank computation problem from the viewpoint of evidence combination and build a probabilistic model for it. Based on the model, we argue that a nonlinear formula should be adopted, due to the correlation or dependence between links. We focus on examining some simple formulas which only consider the correlation between links in the same domain. Experiments conducted on 100 million web pages (with multiple static-rank quality evaluation metrics) show that higher quality static-rank could be yielded by the new nonlinear algorithms. The convergence of the new algorithms is also proved in this paper by nonlinear functional analysis.