Earlier quoted context omitted.
Because to my understanding, 2-tiered search means that the routing search engine scrapes data from the second level search engines and return it to the users. The second level search engines, e.g., Stack Overflow, are usually running by separate entities from the routing search engine, say DDG. If DDG does not own all the second level search engines, how can they get the local indexes and ranking algorithms from the…
The difference with Google is this: 1) Google quality of indexing doesn't have any competition yet. 2) They can calculate a page rank across different domains 3) No single entity can make the same efforts or is so smart to build a similar thing If you follow the 2-tier route: 1) Each entity takes responsability to optimize the quality of search locally. 2) They know their own domain or they can learn how to optimize…
I also agree with you by using distributed sites to optimize the results locally. Actually what I proposed is to make the distributed search from both geographic location and vertical market point of view, as opposed of dedicated sites from you. But they are complementary. The dedicated sites definitely will provide better and more relevant results than a global search engine if Google search was not limited to a particular site.
However, the only thing I don't agree with you is when you said it does not have to be distributed though, the search router can integrate the algorithms from the dedicated sites. Then I think it's not quite feasible since it's not possible for Stack Overflow or Wikipedia to share their algorithms with DDG.
Let me know if I misunderstood you. If you'd like to take if offline, I'll be happy to discuss with you via email. See my profile.