Why You Need Post-Impression Tracking (and Why It's Not Perfect)
In a world where brand advertisers can't rely on clicks to accurately measure the impact of their online display campaigns, a different method of attribution needs to be employed. This is where post-impression tracking comes into play. And this is why advertisers seem to be asking for post-impression tracking more often these days: they need a better way to attribute the results of their ad campaigns.
The Limitations of Post-Click Attribution
Last-click attribution is the oldest and most common method of conversion tracking for online display campaigns. It appeals most to more bottom-of-the-funnel-type performance marketers, or direct response (DR) advertisers. But it doesn't account for more top-of-the-funnel marketing efforts that promote brand searches, among other things.
Brand advertisers that have paid attention to industry reports already understand that less than 1% of the Internet population are even classified as "clickers". Which implies that 99% of people are not clickers. Meaning that brand advertisers need a better attribution methodology to measure the effectiveness of their campaigns. Fortunately, this is possible with post-impression tracking.
Advertisers that understand the power of brand awareness and top-of-the-funnel marketing objectives have already been using post-impression tracking, often labelled as View-Through Conversions, for some time now. It's not a new technology. Google has had it available for years through their AdWords and ad serving platforms. But not every ad platform has the capability to measure view-through conversions. Even fewer with advanced attribution capability. We'll cover that more further down.
The way post-impression tracking works is fairly simple:
- A cookie is dropped on every user that views an ad (which means almost every visitor)
- Even if the user does not click on an ad, the cookie remains with their browser
- If the user visits the advertiser's website or somehow completes the defined "action" for the advertiser, attribution is given to the appropriate campaign
For this type of attribution tracking, you need to understand that a "look-back window" is defined, usually in days, to set a limit on how long, after viewing an ad, an attribution should be counted for any impression.
Naturally, the waters can get muddy very quickly when multiple publishers and ad platforms come into play, which is often the case. It's important to know that post-impression tracking isn't perfect. In its most basic form, it certainly begs many questions.
The Limitations of Basic Post-Impression Attribution
Some of you might already recognize some of the challenges with basic post-impression tracking. It's different from click tracking simply because it's more of a "soft metric", which makes it hard to consider it conclusive data.
For example, consider the following scenarios:
- What if multiple placements on page were purchased at a given time by an advertiser, like in a page takeover. Which ad spot (placement) would the attribution be associated with? Which creative got the most attention? Which dimension was the most impactful?
- If a banner was viewed multiple times, across multiple publishers, do you attribute the conversion to the last banner that was seen? Or the first banner? What about all the other impressions prior, did those exposures play no role in the ultimate conversion?
As you can see, attribution becomes very fuzzy pretty quickly. The need for advanced solutions are necessary to turn basic post-impression tracking from a soft methodology into something more concrete.
The Emergence Of Advanced Attribution
Advanced solutions do exist, which leverage the modern capabilities of "big data", making it possible to gauge the volume of an ads exposure across multiple publishers and placements, with each impression receiving a scientifically-determined percentage of the attribution. Using traditional attribution paradigms, measurement would get complicated very quickly, dealing with fractions of a conversion and so on. With advanced attribution tools, the share of attribution can be shown on a high level, accredited to various publishers and placements and to varying degrees. You could think of it as a way of assigning partial credit to all the touch points prior to an ultimate conversion or action.
Publisher Role in Tracking
Publishers need to understand that their performance will be judged by savvy advertisers in more holistic and data-driven ways, moving forward, across all of their campaigns and channels. With advancements in campaign attribution, publishers will need to accommodate the tracking needs of advertisers, particularly for brands that increasingly rely on post-impression tracking.
Last-click attribution is clearly not a sufficiently sophisticated solution for brand advertisers. Post-impression tracking adds a greater level of insight, but it's also far from perfect on its own. But it's a decent methodology, and it's still better than traditional alternatives, especially for brand advertisers.
To accommodate demanding advertisers, at least at the most basic level, publishers should seek out ad tech vendors that have the ability to do post-impression tracking for advertiser campaigns. In an even better scenario, the vendor should give the people in ad ops the ability to define a custom look-back window, based on the unique business needs of the advertiser. And in an ideal world, publishers and advertisers would agree on a common vendor that could provide the advanced attribution analytics across a multitude of publishers and placements, using sophisticated algorithms, in order to paint an accurate picture for overall campaign attribution to truly give credit where credit is due.
Ratko Vidakovic is an expert in online advertising, real-time bidding (RTB) and performance marketing, with over 15 years of experience in internet technology and digital media. As the Director of Marketing at SiteScout, a Toronto-based software company that builds advertising technology for marketers and agencies, he is focused on marketing strategy and driving growth. He is also the primary author of the SiteScout Blog and Knowledge Center.