What’s the Difference Between Probabilistic and Deterministic

According to a study done by the IAB, “Internet time” is divided fairly evenly among multiple devices: 45% on PCs/laptops, 40% on smartphones and 15% on tablets. And this is a problem for marketers because cookies, the pieces of code traditionally used for aggregating and targeting online audiences, are tied to a single device.

So the question becomes, “How do you reliably target audiences across multiple devices when cookies don’t work?”

Well, two main ways have evolved: Probabilistic Models and Deterministic IDs. And while they both (sort of) solve the same problem, the way they do it is as different as old bunny ears antennae and cable.


Probabilistic Identifiers and the Problem with ID Matching – AdMonsters

WTF is Cross-Device Tracking – Digiday

A Marketer’s Guide To Cross-Device Identity – AdExchanger