Try to add the keyword you are trying on right above and underneath the Adsense code. (Hot tags such as <h1> really make a difference). Also, I always had great success with this, try to add like a parameter to the link on the page even if it is a parameter that is not used. Example: Make "http://www.test.com/index.php" Look like "http://www.test.com/index.php?key=My Keyword" replacing "My Keyword" with your own keyword. You can totally not handle the http parameter in the PHP code. This trick helps a lot, but does not work alone. It really helps when the spider could not decide on what keyword to use. Good luck to all. If you know of other tricky ways, please let me know.
You can believe all you want....Why would you even want to do something like this and risk losing your account?
I dont see the risk. How would anyone know if you are truely using a parameter or not? No one but you can tell what you are using the HTTP parameter for. You can always claim to use for logging!
No trick is safety way to make revenue from adsense. Just create good contents and you will have big smile in next day.
I think adsense is incredibly good at determinning the right ads based on the content of the page that you are not required to take any special measure to generate targetted ads.