I have a leaderboard and banner on my site, and ever since adding the leaderboard, I have had an ad for Yahoo's Auto Insurance page take up the entire leaderboard almost every time I looked at the page. It seems to have raised my cost per impression, but since my site is about sports, it is getting no clicks. Is there anyway to try to make your leaderboard show 4 ads, or should I just block it and other ads I don't like?
Just block it if it isn't working well. I have a question though: Why is your site displaying an auto insurance ad if your site is about sports? Try working on your keyword density and add more related content to see more relevant ads.
It's on the NFL, MLB, NBA, and NCAA, so it's a very eclectic mix. I try not to get too think much about keywords when writing because, at this time, I don't want to sacrifice entertainment value for Adsense and search engines.