Most people don't pay near enough attention to negative keywords. Or maybe they stick in words like "free" or "cheap" but usually that's not enough. Sometimes the total success or failure of your PPC campaign hinges on the proper use of negative keywords.
Here's an example - the keyword "soap." Here are the results you get from the Overture inventory tool:
Searches done in December 2006
Count Search Term
91393 soap opera
63090 soap
41891 soap opera digest
34895 soap central
21779 soap opera central
17220 soap making
13494 soap opera update
13439 cbs soap
12595 abc soap
7271 soap digest
6977 soap city
6794 soap dispenser
5608 soap opera weekly
5178 daytime soap
4974 handmade soap
4778 cbs daytime soap opera
4685 soap making supply
4629 soap dish
4525 daily soap opera update
4344 passions soap opera
4234 soap opera spoiler
4136 all my child soap opera
4099 young and the restless soap opera
3787 soap spoiler
If you're bidding on the keyword 'soap' and using anything other than exact match [soap] it's gonna be real, real hard to make this keyword work. If you sell soap related products, then the list you see here is actually more valuable in terms of the negative keywords it gives you (opera, digest, cbs, daytime) than the positive keywords (handmade, dispenser, dish).
So what you should do is bid this way:
[soap]
"soap"
soap
with negative keywords
-opera
-digest
-central
-cbs
-abc
-daytime
-passions
-children
....and you should go all the way down the list, plucking out as many negative keywords as you possibly can.
When you do that, your CTR on broad match and phrase match will go up, sometimes even double or triple. On a term like 'soap', broad and phrase match will probably not work AT ALL unless you have a very extensive list of negative keywords.
2-3 years ago on PPC, the name of the game was slinging a lot of mud against the wall and seeing what sticks. Today, less is more, and negative keywords are just the kind of 'less' that will sharpen your saw and make you effective.
One last thing: My bookstore book is out on the shelves now. If you give Amazon $16.47 and commit 10 minutes a day to reading The Ultimate Guide to Google AdWords, then 30 days from now you'll be smarter than 98% of all Google Advertisers. Not only about AdWords, but all essential online marketing skills.
For a blow-by-blow explanation of the book, why we wrote it (hint:I'm a self-aggrandizing egomaniac), visit
Perry Marshall, perrymarshall.com
Internet Marketing - Search Engine Optimization - Google
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