We’ve previously talked extensively about one of Mozilla’s core marketing tactics – search engine marketing.  One of the questions we always come back to is: “what macro level effect does this activity have?”  In other words, we know this channel is driving clicks and Firefox downloads every day, but is this effort actually aiding Firefox adoption in some way?

This thought might seem anti-intuitive.  If these marketing campaigns are driving a mass number of clicks and downloads, of course it *seems* as though we’re having some small impact on Firefox adoption.

To test these questions, we recently set-up an experiment much like an experiment we conducted last fall.  Here’s what we did:

• Starting in July, we alternated our bidding on alternate days on a major search engine over a five week period
• Some weeks we turned off our branded search campaigns on Mondays and Wednesdays (to compare with Tues/Thurs during those weeks), and during some weeks we turned off our branded search campaigns on Tuesdays and Thursdays (to compare with Mon/Wed within those weeks)
• For the latter example, a Monday/Wednesday combination with our campaigns left active would have benefited from about 80,000 ad clicks that the Tuesday/Thursday period within that week did not benefit from

Below are the findings when looking at Firefox download numbers on a macro-level, i.e., across all channels, locales, etc.  This is a very large macro-level number, and the traffic seen each day via search engines is only a small part of the overall story, so as one would expect, it’s difficult to see an effect.

Fortunately, we can drill down into the data a little further.  Below are the findings when looking at Firefox download numbers solely through Google.  The numbers represent all downloads through that single channel, i.e., via both organic search results and paid advertisements.

Are these results surprising?

Sort of.

Our previous experiment (with a more limited scale), showed us two things:

• The vast majority of people – who would normally click on our advertisements – will either click on our organic search result or find Firefox via some other method when we turn off our ads
• Having our search campaigns turned on increased the overall pie of daily downloads by approximately 1%

This latest experiment suggests that that initial finding could hold true, but it also makes clear the fact that the answer to our original question (“do search campaigns aid Firefox adoption in any way?”) remains somewhat inconclusive.

We want to make sure we’ve done a fully rigorous job here, so please comment with your thoughts if you have a different take on these numbers and analysis.