A new study published this week finds that most ad execs are unaware of, or do not really understand, duration weighted impressions (DWI), a controversial provision among the industry's proposed cross-media audience measurement standards, which are under public review until June 25th.
According to the new standard, all cross-media ad impressions should be weighted by their exposure time in relation to a fixed 30-seconds denominator. In other words, a 15-second ad that was viewed to the end would account for half the impression value of a 30-second view, while a 6-second ad would register 20% of the impression value.
The controversy surrounding the new standard comes from the implied linear relationship of duration and advertising effectiveness, and the danger that such an oversimplification will take advertising backwards -- especially when it comes to marketing productivity assessment. Let me unpack these concerns.
First, from a research point of view, the relationship between “exposure time” and cross-media effectiveness is murky at best, even in some of the research cited in the new standards document.
For example, in a well-known study of TV exposure time from 1993, Surendra Singh and Catherine Cole concluded that “a blanket comparison of :15 to :30 could lead to misleading conclusions because length effects depend on message appeal.” In 2014, in his research on the “rising cost of consumer attention,” Thales S. Teixeira emphasized that although easier to measure, duration is not a good proxy for attention.
A year later, Goldstein, McAfee and Suri (2015) wrote that “If the total amount of time a publisher gets is divided into slots, two short ads increase memory per slot over a single, longer duration ad.”
MMA´s own SMoX research into the modern marketing mix -- multi-touch attribution (MTA) studies with 14 brands -- have found that duration doesn’t have a consistent relationship with effectiveness. For instance, in our Allstate MTA study, we observed that a 15-second mobile ad was up to twice as effective on a cost basis compared to a 30-second ad -- a finding that in and of itself invalidates DWI.
More importantly, the central theme from all the SMoX studies is that cross-media effectiveness is a complex, multidimensional relationship which cannot be captured by one factor, especially duration. For example, targeting usually works as a multiplier boosting effectiveness of the same creative by 2X-5X.
Ad placements may also impact the effectiveness of the same ad. In one study, a pre-roll video was found to be 80% more effective on a cost basis than an in-banner, auto-play option of the same video ad.
Finally, effectiveness also varies by marketing objective. When foot traffic is the goal, desktop and mobile tend to be more effective on a cost basis than TV, but the opposite is true when optimizing for brand consideration.
H.L. Mencken once said that for every complex problem there is an answer that is clear, simple and wrong. DWI falls in that category. It's appealing because it’s simpler than other approaches to assign cross-media value, but it invites advertisers to use it as a shortcut and to bypass the hard work of attribution.
That's important because as of late last year, at least 6 out of 10 marketers didn't have an MTA solution in place. Those that did were only applying MTA to one-third of their media spend.
So, although the proposed cross-media audience measurement standards clearly do not recommend using DWI as a stand-alone effectiveness measure, marketers will very likely use it as one. And those who do will sacrifice ROI because their reallocation will not be based on real effectiveness data.
For all these reasons, we need to find alternatives to DWI that also work given the current infrastructure of media measurement.
For example, we can’t even track the second-by-second ad that viewing DWI requires in linear TV yet. So, let's continue building granular measurement for all media, including TV.
In the meantime, we need to invest more time in attribution and assess what really drives effectiveness.