Digital advertising impact is created by an interaction between multiple channels. This means it can sometimes be difficult to track your online sales funnel and interpret analytics. Attribution modeling is about understanding which ads, referrals and searches played a role in getting a customer to convert. Here are answers to some of the most commonly asked questions about Facebook attribution.

One thing we hear on a weekly basis from our customers is that attribution is causing them grey hair and often makes Facebook look really bad compared to other channels, while Facebook’s own metrics show a very nice ROI. The main culprit tends to be Google Analytics, which most advertisers use to get an equal view of different online channels, as it shows multiple channels measured with the same method. While Google Analytics is an efficient and, even better, free and easy tool for keeping track of all of your online activities, it is very important to understand what it actually tracks and what it doesn’t.

There are three main reasons Google Analytics shows much lower conversion numbers compared to Facebook. We’ll deep dive into those in more detail below.

• It gives full credit to last paid click regardless of channel.
• It’s not able to track Facebook’s view-through conversions.
• It’s not able to track cross-device conversions.

Which interaction gets the credit?

Facebook attributes a conversion to the last click the user has made on a Facebook ad (click-through or post click conversion), or, if no clicks happened, the last ad they’ve seen before converting (view-through or post view conversion). Google Analytics, on the other hand, gives credit to the last paid click by default, regardless of the channel, if any have happened.

For example, a user clicks on a Facebook ad for an interesting product but decides not to buy it. The next day he changes his mind, googles the product and clicks on a search ad; ending up on the same website to make the purchase. Facebook takes full credit for the sale, so does Google Adwords. For Google Analytics only the last click matters, so Facebook gets nothing.

Which interactions count?

While Google Analytics can track impressions of Google ads, there’s no way to track Facebook impressions in Google Analytics. Facebook’s default attribution window is 28 days post click and 1 day post view, but both can be selected for either 0, 1, 7 or 28 days. This means that anyone who saw an ad but did not click on it during the timeframe will count as a conversion on Facebook but not on Google Analytics. To get the numbers closer to each other, you can choose to look at only post click conversions in Facebook reporting.

Which devices count?

One of Facebook’s biggest advantages over its competition is the ability to link actions to users instead of cookies. In practice this means you can track and target the same user across all their browsers and devices as long as they are signed in to Facebook. Google Analytics, on the other hand, relies solely on cookies which means all tracking happens inside the same browser where the cookie was dropped.

Example: A user clicks on a Facebook ad on their mobile and finds something they want. Later that night they go directly to the same site on their computer to finalize the purchase. Facebook counts a cross-device conversion, but Google Analytics shows the source as direct traffic. To get these numbers closer, you can look at Facebook’s cross-device reporting and only count the conversions happening on the same device.

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