He was joined by Twitter Senior Director of Product Revenue Kevin Weil and Google VP of Display Advertising Products Neal Mohan.
They all agreed that ads these days need to be cross-platform and work well on PCs, tablets, and even wearable devices like Google Glass. But they had different ideas of how to measure the success of a digital marketing campaign.
Ads these days are measured by impressions (how many ads served up), clicks (how many people click), and conversions (how many people buy). Those are good as far as they go, Google's Mohan said, but specifically measuring what brands care about is still a huge obstacle.
Facebook's Rajaram suggests that companies should focus less on engagement and clicks, and more on how people are being exposed to ads because "there's really no correlation between clicks and whether people actually convert."
Studies have shown that even if people don't click on ads, just seeing the ad will influence a future purchase, similar to way ads work on television. This is called "demand-generation," which aims to plant ideas in your head and doesn't intend to elicit an immediate response.
Rajaram went on to say that digital advertising just doesn't work very well.
"For the last decade, the model has been broken," Rajaram said. "We need to move towards a more sophisticated, multi-touch model and figure out how to accrue value at each touch point."
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