Molly

Stacy made a good suggestion with looking at your traffic logs to figure out what the search term was which drove users to your site in order to find a list of good negatives. Another way would be to tailor your copy to make sure users wouldn’t be confused. I would imagine in the case of the “used sun” the ad should have mentioned Sun servers to avoid people thinking it was used Sunfires.

[used sun] ** 1.44
“used sun” ** 0.99
used sun ** 0.25

Point is to pay more for what you know you’re buying and less for what you don’t know. Also, if you are buying broad matches, it’s worth using Google’s keyword tool with the “Use synonyms” box checked to get an idea ahead of time as to how the system might expand the broad match. In the case of /used sun/ I’m currently seeing expanded keywords like:

used cars for sale
used sunfire

Clearly, Google’s keyword system is expanding “sun” to “sunfire” and then equating that with “cars” so if I had keywords /used sun/ broad match, I’d definitely add these negatives right from the start:

-car
-cars
-sunfire

It is useful to use (expanded) broad match, but it’s worth minimizing risk by setting those bids much lower than exact or phrase, so you’re not paying for clicks for poorly matched keywords. As Stacy mentions in the video, it’s important to scour the server logs periodically to see what actual keywords the broad matches are bringing. Then, new negatives and even new exact and phrase matches can be added to the ad group. This way, the keyword list can evolve over time but you’re not paying high CPCs for extraneous keywords along the way.

Anyway, haven’t seen too many people dig into expanded matching so figured it’d be worth mentioning how important it is to recognize that it is the default way Google handles keywords and advertisers need to deal with it appropriately.