Cross-Device Targeting: A Fairy Tale Idea

An eMarketer study shows that few cross-device targeting solutions are effective, which leads to the question: Is cross-device targeting, still just a fairy tale?

Kaushansky explains the challenge with two cross-device targeting models as examples: "probabilistic" and "deterministic."

The "deterministic" methodology leverages users' data such as social log-ins, email address or e-commerce. For example, Facebook's Atlas ad server allows marketers to syndicate Facebook log-ins and target users across mobile, tablet, desktop and laptop.
Although "deterministic data" is a strong indicator, it's not 100 percent accurate. Chances are a user may log-in to a platform from another person's device or that user may not be a subscriber, and thus there's no log-in detail available.
On the "probabilistic" side, marketers rely on devices rather than users' log-in data.

"Companies like Drawbridge and Tapad collect device IDs to solve cookies' lack of tracking functionality outside desktop. With the device IDs, they are able to identify associated cookies to a device, using WiFi signals, location, etc. and probabilistically match the device to a user," Kaushansky explains.
http://www.clickz.com/clickz/news/2413004/cross-device-targeting-a-fairy-tale-idea