The Forgotten Side Of Viewability

mattscharfupdated“Data-Driven Thinking” is written by members of the media community and contains fresh ideas on the digital revolution in media.

Today’s column is written by Matt Scharf, manager of display media operations and analytics at Adobe.

The topic of viewability has infiltrated our lives. Viewability vendors flood the marketplace as marketers take steps to measure their campaigns. If you’re one of them, you’re headed in the right direction, but you’ve only just scratched the surface because measuring viewability is just the bare minimum.

Viewability poses two problems to marketers. They’re both equally important but only one gets discussed. Meanwhile, the other smolders behind the scenes, dragging down the efficiency of your media.

The one you’re probably aware of because every one talks about it is the inventory quality problem. Simply put, marketers waste budget by paying for out-of-view impressions when they shouldn’t. This will take a long time to solve. The industry needs to figure out the economics of moving away from the standard CPM buying model and replacing it with vCPM, where only “viewed” impressions are paid for. And once that happens – if it ever does – you will have waited a long time to solve only half the problem.

The other half is the inventory attribution problem. It’s the unspoken dilemma in the industry, the forgotten side of viewability. Marketers attribute conversions back to media that was never in view by the end user. In the same way that marketers pay for all out-of-view impressions, they also assign credit to out-of-view impressions. There is no argument to be made for an ad to receive credit for driving a conversion if the end use never saw it. But this happens – frequently. And to make it worse, marketers optimize towards these erroneous conversions.

Why? Most attribution platforms don’t consider Viewability as an input to inform attribution.  If they have that capability, most advertisers are not taking advantage. The standard approach is to simply look at whether a cookie was served an ad prior to a conversion. Then they consider all those events viable for attribution credit, regardless of whether they were in view by the end user or not. For example, if there were three impressions served to a user prior to converting but two were never viewed, the standard approach by attribution models is to consider all three to be eligible for attribution. Yet, in reality, only one impression had anything to do with that conversion.

To quantify the impact to marketers with a very simple example, let’s assume you have $100,000 of incremental budget to drive as many cost-efficient conversions as possible. You’d evaluate the historical performance of all media placements to see where the $100,000 would be best invested.

Here are two placements to consider. Without using viewability data to make your decision, you’d choose Placement 1 because it can drive orders more efficiently. A $35 cost per order is better than $40. That’s an easy decision.






But there’s a better way. By adding viewability rates with some simple math, we have a new metric to address the forgotten side of viewability: viewable cost per order (vCPO). It’s the attribution version of vCPM, which is used to address the inventory quality problem.

To calculate vCPO, you effectively discount the number of orders by the view rate. If only 48% of impressions are viewed, we should only take credit for 48% of orders.


We now have a completely different view on performance above. The proper choice is now Placement 2 due to the higher view rate. By simply incorporating viewability into performance considerations, you’d drive 129 additional orders by choosing Placement 2. And the monetary value of those additional orders is $8,643 (129 orders x $67, the amount you’re paying to drive the orders).

That’s just a small example. Imagine how big that number would be for an entire campaign.

This is a good step toward evaluating your media performance through a new lens by applying your viewability data. But it’s a flawed solution and therefore temporary until the industry solves for what it really needs.

What The Industry Really Needs

Attribution platforms need to ingest viewability data. Proper attribution looks at the media touches a cookie was exposed to prior to converting, then weighing which touch is the most causal and worthy of credit. The above example of excluding a percentage of total orders is too arbitrary. The proper way to do this is to exclude out-of-view events from attribution consideration.

And therein lies the problem. Attribution models aren’t ingesting viewability data so they cannot exclude the events that are not in view. The two ad tech platforms best positioned to push the industry forward are ad servers and multichannel attribution platforms. The solution can be as simple as a file with binary events – a series of 1s and 0s in a successful path to conversion. All 0s are out-of-view events that should be excluded from attribution consideration.


Which Ad Servers Will Be First?

Ad servers already serve ads and provide attribution for most marketers. All they need to do is measure viewability, too, and exclude out-of-view events from attribution consideration at the cookie level. They can then provide two columns for conversions: one with the standard approach applying credit to “served” impressions, and another column showing conversions for “viewed” impressions, after excluding out-of-view impressions.

Marketers will not only thank them for being able to consolidate the number of ad tech vendors they use, but they will also do a back flip when they can optimize more intelligently and avoid juggling another data source from yet another viewability vendor.

Could multitouch attribution platforms fill the void? They are also well-positioned because they’ve already mastered the complicated process of cookie data ingestion from multiple channels. Incorporating viewability into your multitouch attribution model is a big advantage.

This is a gaping hole in the marketplace and a huge opportunity being missed by ad tech platforms. Who will be first? In the meantime, there is always the vCPO calculation. It’s better than nothing.

Follow Matt Scharf (@Matt_Scharf), Adobe (@Adobe) and AdExchanger (@adexchanger) on Twitter.

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  1. Jeff Burkett

    Great article Matt. This is a problem that many are ignoring. If you talk to any ad network/RTB media seller who is willing to be honest with you, they will tell you that the un-viewed impression is actually driving 90% of their success. Its fraud. They pay high CPM’s for some quality inventory to drive clicks, but spend the majority of the budget on cheap crap inventory for the purpose of spraying conversion pixels every where. Agencies ignore this because the campaigns are ‘working’ and the practice justifies huge budgets that are spent in digital.

    If buyers adopted what you recommend here, there would be drastic changes in how digital budgets are allocated and a large chunk of the ad network/RTB Media Sellers would be out of business quickly.

  2. Matt –

    You are absolutely right and your thoughts are well laid out. I would actually contend that viewability is not forgotten; rather it is one of the simpler challenges in a robust attribution solution. Currently a few of the standalone attribution solutions including Adometry (my company) incorporate viewability as part of the equation. For us, our heritage is ad verification and analytics so measuring and excluding non-viewable impressions as part of the attribution calculations is an obvious and natural approach – especially when you consider as much as 50% non-viewable. Granted, their remains challenges with nested iFrames and new formats (video, in app, etc.), but those issues are continually being worked by the industry and some is always better than none.

    Ultimately, I would expect viewable impressions to table stakes across the ad tech ecosystem. To this point, last year Google fired a shot across the bow by announcing Active View metric within DFA and allowing some buying of guaranteed on-screen impressions. It is still early to see how other ad giants respond, but the pressure is on.



  3. A very thought provoking read, Matt. Awesome stuff.

    I may need my hand held on something, though. I’m having a problem with the comment:
    “If only 48% of impressions are viewed, we should only take credit for 48% of orders.”

    This references the “simple math” indication you state, and I think this is fundamentally a gross assumption. A pure 1:1 ratio of vCPO:#ofOrders is not plausible, it seems as though it’s done to help illustrate the more general and overlaying argument that ‘unviewable impressions shouldn’t be paid for, or calculated’. The math is being manipulated through the argument’s context. I see where Matt is going, and I agree with the logic, but the hypothetical yet real-world example assumes an incredible amount to create a vacuum of support. I’d like to see a more concrete example before I’m nodding my head.

    Also, if anyone can reference great material in support of the notion that online marketers have some sort of “right” to only pay for viewed media, I’d welcome the link/material. Marketers pay for an opportunity to be seen/heard, and they pay accordingly by taking into account an ad unit’s likelihood to be seen (i.e. why ATF ad units are sold direct and BTF typically are not). Will radio now only pay for the audible ads that are heard? Will TV now only pay for commercials that are verified to have bodies in the room when shown? I’m all for adding an optional product to the mix that only requires payment for verified viewed impressions, and is priced at a premium, but making viewable impression offerings the only standard and status quo of the industry? I don’t see the validity or support the argument.

    Happy to eat crow and be convinced otherwise.

  4. Sachin Ahuja

    Matt: Nice article & if my understanding is correct than how does publishers gain from this because if they earn money for only completed view of the total number of impressions in the campaign then what happens to the rest inventory which though was shown to the user but he/she skipped it leading to an incomplete view? Won’t revenues of publishers get impacted because of this?

  5. Matt Scharf

    @ Samuel, thanks for your thoughts on the article. You’re spot on about the lack of a 1:1 relationship between view rate and conversion acceptance in relation to my proposed (and temporary) vCPO calculation. To your point, it’s applied at a level higher than the cookie/event level. As a result, the methodology is far from 100% sound. But much better than taking no action. I reference the fact that it’s a flawed approach, due in large part to a lack of event level integration of Viewability data in commonly used platforms such as enterprise level ad servers who predominantly serve as the immediate source for conversion attribution for display marketers. Without the right solutions in place in these commonly used platforms, I propose marketers include a knowingly flawed ancillary metric (vCPO) that is better than ignoring the view rate data altogether. The benefit to marketers is having an additional metric to make more intelligent decisions on media spend due to directionally more accurate insight into performance.

    Multi-touch attribution platforms that are ingesting multiple data feeds at the event level are well poised to offer this solution to marketers such as what @Casey is referencing. In contrast, this idea does warrant a 1:1 relationship by excluding out-of-view events.

    Regarding the “right” to pay for only viewed media, you raise a compelling argument when comparing digital to other more traditional marketing mediums. I think digital media was born from data and its value proposition is measurement. As a result, it should be held to a higher standard by marketers, end users, and inventory providers alike. While other mediums may have a more tolerant understanding of their ad exposure, I’d argue digital marketers have a right to demand more. 100% assurance, maybe not due to ad tech limitations that @Casey outlines. But certainly more, much more.

    As @Jeff suggests, we need to hold parties accountable for better inventory. Action can be taken in this medium much easier than others. Then marketers need to measure the impact.