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The sizes of hidden data sources are of great interests to public, researchers and even business competitors. Estimating the size of hidden data sources has been a challenging problem. Most existing methods are derived from the classic capture-recapture methods. Another approach is based on a large query pool. This method is not accurate due to the large variance of the document frequencies of queries...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.