The share of an ad's results that wouldn't have happened without it: for a brand ad, the clicks and orders that wouldn't have come anyway.
Every brand ad gets clicks, and most are cheap. Incrementality asks how many of them, and the orders behind them, would have happened without the ad. A shopper who searched your name and would have clicked your organic listing anyway adds nothing by clicking your ad instead. One who would have clicked a rival's ad, or an affiliate's, is the one you're paying for.
- Monthly spend at £0.18 a click
- £3,600
- Clicks that would come back organically (90%, assumed)
- 18,000
- Clicks the ad really added
- 2,000
- Cost per extra click
- £1.80
Published answers differ because the conditions differ. Google's pause studies found about half of ad clicks were incremental when the advertiser ranked first organically, and 99% when it had no organic listing on the first page. A study of a very well-known marketplace, with few rivals on its name, found its brand ads added almost nothing. Studies with rivals present found more at stake.
Only a test on your own brand answers it for you, usually a geo experiment. The guide to bidding on your own brand goes through each study.
Google's own help and policy pages first.
- Chan, Kumar, Ma and Koehler (2012): Impact of Ranking of Organic Search Results on the Incrementality of Search Ads
- Blake, Nosko and Tadelis (2015): Consumer Heterogeneity and Paid Search Effectiveness: A Large-Scale Field Experiment
- Simonov, Nosko and Rao (2018): Competition and Crowd-Out for Brand Keywords in Sponsored Search