It's hard to measure the cost of errant clicks on one of Google's AdSense ads. But a small change in the ad's clickable area should help advertisers avoid paying for clicks users never intended to make. That's the theory behind recent changes made by Google to its popular AdSense program.

To help address the issue of errant clicks, Google has resized the clickable area in an AdSense ad, making only the text clickable. In the past, the entire body of the ad could be clicked.

A post on Blogoscoped that illustrates the changes hypothesized revenue from AdSense would likely drop. However, many see errant clicks as a flaw in the AdSense system, and Google has said it expects the change to improve quality for publishers, users and advertisers.