3. Advertisers are not using image ads for keywords associated with your site, or are setting bids too low to show on your site.

I see image ads on other sites in my niche so perhaps it is that they are setting bids too low to show on my site.

What determines if a bid is too low to be on my site?

I am new to adsense and appretiate feedback!

Thanks.

Size of the ad block is definitely one factor.

Overall I'd say you're better off. I allow image ads, because it creates a larger base of potential advertisers and because I sometimes get hit by a lucrative CPM campaign, but in general I'd say text ads look better and are better targeted and probably pay better. And don't get me started on how much I hate Flash/multimedia ads.

Thanks jomaxx. I have read on this forum how many people feel text ads are the way to go. I won't worry too much about the image ads.