Using Capture-Recapture approach estimate size of Web databases
用Capture-Recapture方法估计Web数据库大小*

In order to estimate the size of Web database, this paper proposed the Capture-Recapture based estimation methods that filtered out two words intimate and rejection cases. Submitting attributed high-frequency words in the text box of query interface, using the returned result, in the intersection of two results analyzing the independence of two sampling, filtering the dependent couples, and then using Capture-Recapture method estimated the size of Web database. In the simulated and real environment for the experiment, the bias and the volatility of the method are smaller.