Why does Google show multiple results from the same domain?

Matt's answer:

Today’s question comes from San Francisco, California. And the question is, why does Google continue to present multiple results from one domain on a search result? Does it really benefit the user to have seven results from Yelp? OK. This is a really interesting question. I want to go ahead and cover it in depth and give a timeline, because of all the questions that people ask, this was one of the topics that bubbled up amongst a lot of different questions. So I want to make sure I cover it well. In the early days, we had no restrictions at all. We would completely score things. And if we saw antique green glass ranking from one domain, you could get tons and tons of results all from one domain. And that was kind of a bad experience. And so we introduced something called host clustering. Host clustering means for each hostname, so like per subdomain, you only get two results. And it was interesting because we then saw people, spammers, a bunch of different webmasters, adapt and say OK, do a bunch of different subdomains. And then you can get two results from one hostname, two results from another hostname, two results from another hostname. And they can get back to crowding up the whole results page again. So we changed things again, because we do want diversity in our search results. And we made it such that, OK, you can get one result from a domain and another result from a domain, and then progressively new results from that same domain get harder and harder for them to rank. So if the only good results are on a certain domain, then sure, you might see a lot of results from that one particular site again. But otherwise, you’d see a little bit more diversity, one or two results, maybe three, possibly four. But then you’d see results from other domains. And that was pretty good. And that was the world that a lot of people were used to. And then we made another change not too long ago, within the last couple years, that basically said, look, if somebody’s searching for rental cabins in Tennessee and there’s a really good website about that, something that we think really matches the query very well, then it might be helpful instead of only showing a few results from that domain to show more results from that domain. As we’ve seen, a few people are unhappy about that, because if you’re looking for a nursing care home in the United Kingdom and you only get results from one or two domains, then a lot of people felt like we weren’t returning the diversity that we should. And so we actually made a change that made it such that on the first results page, you’d be a little more likely to see diversity. And we weren’t as worried about the second or the third results page. And so a lot of the complaints that I’ve seen in the last few months have actually been along the lines of, do this search for jobs in India or wherever, and click to page three, and then you’ll see a lot of results from one domain. And on one hand, I understand that that could be frustrating. On the other hand, if something happens on page two, three, or four, fewer people are seeing it and so it’s not considered quite as much of a crisis or something that we’re really worried about. However, it was kind of interesting. We saw enough questions– there were at least four or five questions out of the 337 that we’ve seen so far that asked about this specific topic. So I went back and I found a complaint that people had done from a few months ago where the result was a cluster of results all from one domain and it was on page three. And I dropped an email to the engineer in charge and said, hey, people are still kind of unhappy about this. Is there any new update? And he replied back by email that there was a new update. And so this hasn’t launched yet. But it has been approved by the quality launch committee meetings. And it’s in the process of rolling out relatively soon. And it basically says, once you’ve seen a cluster of, say, four results from a given domain, as you click on subsequent pages, we won’t show you results from that domain again. So that should help improve the diversity. We might still show multiple results from one domain if we think it’s a really good match for that query. But at least you hopefully won’t see it over and over and over again as you dig deeper in the search results. So it’s always an ongoing balance. We want to have diversity on one hand. And on the other hand, if there are really good results from one particular authority on the web, we want to return the results from that authority as well. The main thing I want to say is, this does continue to evolve over time. And I do appreciate the feedback. All the people who either send me a tweet or drop me an email or send me a screenshot and say, hey, this is a bad search result, that’s really helpful, because I can forward that on to one particular engineer in this case or to a team if people are worried that titles are not being computed correctly. And we do listen to the feedback. And we try to improve things. So I think that we’ll have a little bit of a better set of search results regarding this particular topic in a pretty quick timeframe. But keep sending us feedback, because that just helps us make better search results for everybody.

by Matt Cutts - Google's Head of Search Quality Team

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