Why Does the Same Local Search Produce Different Results?

If you do a local search on Google, and then do the same search on Google Maps, there’s a good chance you’re going to get different results. I started writing about this way back in last July, and then asked Jon Glick about it a few months later.

This kinda flew under the radar since then, but became a Big Issue again late last month when Google added Maps/Local results to their main SERPs for anything remotely resembling a local query.

Mike Blumenthal did some digging on this and wrote a post about the findings: In 12 query samples, the results were different between Google and Google Maps 50% of the time.

I joined in the discussion on Mike’s blog, as did Bill Slawski — who followed up with a great post in which Bill uses his patent-based research to suggest this possible reason for the difference:

…I suggested that the difference was because there was a difference in the maps shown, and the sizes and boundaries of those maps.

Bill’s analysis is great, as always. But I have a problem with the whole premise — not with what he’s saying, but with what Google might be doing:

…the difference was because there was a difference in the maps shown, and the sizes and boundaries of those maps.

The obvious question here is … Why?

If I run the same query on Google and on Google Maps, why do they need to show different maps? When searching for [italian restaurants in Seattle], we can presume my intent is the same whether I’m using Google or Google Maps. Yet, there’s a good chance I’ll get different results from one to the other.

Again … why? When I asked Jon Glick about this — Jon’s a former Yahoo Search exec who speaks with Bill on the Search Engine Algorithm panels at SES — he suggested it’s because different data sets are involved:

The general web search and the local search are searching different corpora and using very different algos. When “seattle hotels” is entered into the general search, it’s the pages with the most keyword hits, highest connectivity, etc. that rank well. This is just like any other general search query and the algo doesn’t have any semantic understanding that the search is local; the search is just keywords, and the pages are just keywords and links.

In contrast, the local search functions more like a yellow pages directory. It ignores “authority” from sources like link connectivity and instead relies on some basic structured data like the proximity of the hotel to Seattle’s city center. It’s searching a set of hotel listings as opposed to pages that have been crawled from the web.

I think there’s legitimacy to both Jon’s and Bill’s suggestions, but the fact that I may get different results for the same query is, in my way of thinking, a failure. From a user perspective, I think it’s especially jarring to run a local search on Google, see the new display showing the Top Three listings, and then click the “More Results” link and … BAM! … suddenly the Top Three aren’t the Top Three anymore.

How is that a good search experience for the average user?

[tags]local search, google, google maps, bill slawski, mike blumenthal, jon glick, fix your local algo google because it looks broken[/tags]