It's all right to select more than one measurement. After all, your company may have more than one business goal. Mike Galgon of Avenue A, an online ad agency, suggests creating an index by weighting your metrics according to importance. Many have ROI features that use cookies to track a user from impression all the way through purchase. Increasingly, advertisers are able to get an even more complete picture by combining ad serving data with Web site tracking tools.
Many companies opt to build in-house measurement systems.
Integrate the referring URL from your Web logs with the rest of your tracking and measurement system. While in-house systems may seem less costly, they can quickly become complex and difficult to manage. Moreover, keeping up with the latest technology offered by third-party providers can be daunting. Another benefit of third-party ad serving is that since your ads are stored and served centrally, you can implement changes to your ad campaign immediately, rather than waiting for the publisher at each ad site to make requested changes. Many third-party ad servers have ROI features that use cookies to track a user from impression all the way through purchase.