Hi, In a google search some ads appear at the top between the search box and the search results. And others appear in a column on the right. How does Google decide where to put each ad? Regards, fcmisc.
Ad placement is determined by factoring in an ads CTR and max bid. It seems to me to that competitive (lots of ads) markets tend to show ads at the top and right, while less competitive markets (few ads) tend to only show in the right. Generally speaking I think they just tend to mix up the presentation of the ads in on the serps to help increase ctr for the advertisers.