• by Shankar Gupta , December 20, 2006

Search giant Google Tuesday issued a clarification of its Quality Score rankings, which are used to calculate an advertiser's minimum bid.

The guidelines, which were previously somewhat vague, now instruct advertisers on how to improve their scores. The advice includes instructions to link to the page on their sites with the most useful information about the service or product being advertised, ensure that the landing page is relevant to their ad's keyword and text, distinguish sponsored links from the rest of their content, and refrain from building landing pages that merely consist of more ads.

Google began incorporating quality scores last year, based only on the ad's prior performance. This summer, Google refined its methodology by taking into account landing page quality. When the landing page quality was incorporated into the quality score, the only guidance given to advertisers on their blog was a somewhat cryptic statement: "From time to time, we improve our algorithms for evaluating landing page quality (often based on feedback from our end users), and next week we're launching another such improvement."

Separately, Google Tuesday banned AdSense publishers from displaying images near their text link ad units. According to a statement by the search giant, consumers were mistakenly clicking on the ads--thinking the images were associated with them.