FORT LAUDERDALE  –  If you want to price digital advertising appropriately, don’t just look at the rapidly-growing supply of inventory, look beneath the surface for what is really real. That’s according to veteran ad exec Irwin Gotlieb, the chairman of ad group GroupM.

“Supply measured without taking in to account things like viewability and bought fraud wasn’t real supply anyway,” he tells Beet.TV in this video interview. “We refused to accept the IAB’s viewability standard, we have our own definitions, we have our own technologies on fraud prevention.

“The price of an impression that is 100% viewable and largely fraud-free is not going to be the same as the price of an impression that is fraught with those issues.

“If you’re going to compare costs across different media types, you’ve got to eliminate the bull before you have an apples-to-apples comparison.”

We interviewed Gotlieb at the recent Beet.TV executive retreat in Florida.