Share Of Attention: Advertising’s Newest Time-Based Metric

Advertising’s “thing” is more nebulous, but at its core the advertising industry is about buying and selling attention, so it makes sense that the metric of sale for advertising should attempt to measure attention. Today display advertising uses the impression, but it does a poor job of yielding a consistent amount of attention.
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The right question to ask is: “Is viewability the right way to measure attention?”
http://adexchanger.com/data-driven-thinking/share-of-attention-advertisings-newest-time-based-metric/