The Publisher Center is available in English only at this time, but all publishers can use the tool. The Google Ad Planner Publisher Center lets publishers contribute directly to the site data found in Google Ad Planner. Web masters can specify their site descriptions, content categories, supported ad formats and sizes, and share their Google Analytics traffic data in Google Ad Planner, which will allow for better targeted ads tailored to the site specifics.
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According to Google;
The Publisher Center enables publishers to contribute directly to the site data provided in Google Ad Planner. Website owners can specify their site descriptions, content categories, supported ad formats and sizes, and share their Google Analytics traffic data in Google Ad Planner. With shared Google Analytics data, we can supplement our traffic estimates with actual, site-measured data from the publishers themselves. In turn, you'll have access to more robust and accurate information in Google Ad Planner to make better-informed decisions about which sites to include in your media plans.
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