View-Through Attribution (VTA)

View-through attribution (VTA) gives credit to ads that a user saw but didn't click on, if they later convert within a specified time window (typically 1 day). The theory is that seeing the ad influenced the purchase decision, even without a click. VTA is highly controversial because it's prone to inflating performance metrics. Many users who saw your ad would have converted anyway, and the ad view had no causal impact on their decision. This is especially problematic for retargeting campaigns, which target users already familiar with your brand. Facebook and other platforms include VTA in their default reporting, which is why platform-reported ROAS is often higher than actual ROAS calculated from your ecommerce platform. Many sophisticated advertisers exclude VTA from their performance calculations or weight it much lower than click-through conversions.