Without Exposure, Viewability Is Flawed


Written by:

Tim Webster

Co-Founder and CSO, The Exchange Lab

A  report  by the World Federation of Advertisers revealed that only half of display ads are viewable. While at first glance this finding may cause serious concern for advertisers, when put into perspective and considered in the context of overall ad performance, it should not be all that shocking.

The broadly accepted definition of viewability set by the Media Rating Council (MRC) states that 50% of an ad’s pixels must be in view for a minimum of one second. Yet the arbitrary nature of the standard is problematic: for example, 49% of an ad may be in view for 10 minutes and 100% of another for 0.99 of a second. Using the MRC gauge, neither would count as viewable, although both may have made an impact.

Such is the frustration with these limitations that many key players now set their own guidelines. For instance, GroupM works to an enhanced standard of 100% of pixels in view for one second, while Facebook classifies an ad as viewable when the entire ad – from top to bottom – has passed through a user’s screen in News Feed. Neither is perfect, but they do raise the bar.

Consequently, there is no universal standard for viewability quality and discussions around how to resolve this are distracting industry attention from a core priority: maximising advertising efficiency. Often, viewability is included as a stand-alone key performance indicator (KPI), but this is ill-advised. Just because an ad is classed as in view, doesn’t mean that it influenced the user. To boost value for advertisers and audiences, it’s crucial for campaign measurement to start looking beyond baseline viewability.

A flawed approach

The main issue with deploying viewability in isolation is that it can adversely impact overall performance. More specifically, if campaign optimisation is solely geared toward achieving a higher percentage of ads in-view, the result will often be a negative effect on other campaign measures. For instance, analysis of potentially more important considerations — such as cost per conversion — may show that optimisation of viewability has directed large portions of budget to more expensive inventory. While this inventory may have been seen, it will not necessarily deliver the uplift in performance that offsets the increase in cost.

Clearly, there is a need for measurement to include metrics that can assess which ads are worth investing in — for example, exposure time.

A new approach to measurement

Total exposure time analyzes how long ads have the opportunity to be seen by users, instead of simply whether they are viewed or not. This is important because it provides a way to understand viewable quality, and also shows the correlation between time exposed to ads and outcome achieved.

It is essential for advertisers to take the quality of viewability into account when evaluating performance and ensure that it is used in conjunction with metrics that assess actual outcomes. For example, viewable cost per acquisition (vCPA) and viewable cost per thousand impressions (vCPM) measure essential aspects of performance against whether ads had the chance to influence their intended audience. Similarly, by using exposure time, advertisers can trace the effect of viewability quality on campaign outcomes and cost. Armed with this insight, they can then optimize to the most cost-effective quality ad exposure and allocate spend to the channels and platforms that deliver against their business needs.

Marketers must, however, remember to keep ad standards high. Exposure time measurement will only provide a reliable basis for future efforts if messaging is compelling. An ad could be in view for half an hour but if the creative is uninspiring, served to a user who has no interest in the content, or delivered in an irrelevant or inappropriate context, it will still fail to perform.

With just half of global display impressions passing the MRC standard and the industry in disagreement over the criteria, viewability on its own as a performance metric is in question. Used in isolation, viewability may negatively impact campaign performance, which is why it must be used in conjunction with other metrics to provide a more meaningful understanding of outcome.

By fully embracing this measurement mix, advertisers will understand which ad placements and targeting reach and influence consumers, allowing them to accurately place budget to the correct channels and ultimately create a tailored campaigns that drive effectiveness and business outcomes.

Written by:

Tim Webster

Co-Founder and CSO, The Exchange Lab

Download your free copy of our Fall Playbook


Yes Please!

Keep up to date with the latest industry news and events.

Exchange Lab Win Digital Trading Award


Programmatic – Shape Up Or Ship Out


We’re Drum Digital Trading Awards Finalists


can we tell you a secret?

We've got tip sheets, videos and more
just for you...

Take me there!

Privacy Preference Center

Close your account?

Your account will be closed and all data will be permanently deleted and cannot be recovered. Are you sure?