if Google expanded the size of their main index?
if Panda were a method by which Google defines if each url will be placed in supplemental index or if will be placed in main index?
I know, I know, the supplemental index and removed (hidden?) long time ago, but..
-why many sites loss only long tail visits? (very significant!)
-why many sites with original content are affected? (very significant!) user experience data?
-doesn't Panda penalized duplicate content? Not, The scrapers still in search results.
Is Panda a filter that has been designed only to spot what it believes are low-quality pages?
Main Index Ratio of all sites that are affected (3 sites affected of 12) is less than 10%.
Calculating your supplemental index ratio (roughly)
Total Pages Indexed = site:www.yoursite.com
Pages in the Main Index = site:www.yoursite.com -inallurl:www.yoursite.com
Main Index Ratio = (Pages in the Main Index x 100)/Total Pages Indexed
Now there are fewer number of landing page and there are fewer number of keywords for each url (in my sites), this the same happened in caffeine update. The long tail are distributed between a greater number of competitors. These new sites ranks the pages more related semantically/syntactically with searched keywor.
I've noticed that changes in the serps, that could means that there are changes in some factors of the algorithm, or could be a recalculation with the new data.