Ad filtering is a mean for you to get rid of some un-desired ads appeared on you pages. After logging in your adsense account, under the "Adsense Setup" tab, you should be able to find the "Competitive Ad Filter" sub-menu. There you can put as many as 200 " ad urls" that you want to filter.
So, what kind of ads should you get rid of? and why ? Below are a few examples:
- ads from your competitors - if your site is running some sort of business, sure you want to avoid ad from your competitor.
- irrelevant ads - the resonale is that if the ads are irrelevant to your page content, most likely your visitor will not click on them, so why wasting the space for them?
- MFA ads - MFA ads are usually low paying ads (due to their biz model), so it may be a good idea to get rid of them. Another argument is that driving your site users to those "empty content" site is hurting your user's interest and your site's reputation.
