Google calls time on last-click attribution


Google’s buy-side network Google Ads has announced in a blogpost that it is switching its default from last-click attribution to a more modern “data-driven” attribution, an alternative technique that uses machine learning to try to better understand how each touchpoint contributes to conversion.

Why it matters

While there was some evidence that for large brands last-click attribution was simply inadequate – in the case of Adidas encouraging an over-investment in performance advertising – and that there were clearly better techniques, data-driven attribution was closed off to many smaller advertisers due to minimum data requirements. Now these capabilities are becoming more accessible as they become standard.

What will happen

  • The rollout will start in October, with the aim of all Google Ads accounts using data-driven attribution by early 2022.
  • As well as data-driven attribution, users will continue to have the option to keep using any of the five other rules-based models: last-click, first-click, linear, time decay, position-based.
  • Vidhya Srinivasan, VP/GM Buying, Analytics and Measurement at Google Ads told AdExchanger that as more advertisers start using the data-driven method, the quality of Google’s modelling will improve. This is crucial when third-party cookies finally go, as the machine learning can help to fill gaps in the data.

Key quote

“Advertisers around the world have seen better results by switching to data-driven attribution. When combined with automated bidding strategies, data-driven attribution can drive additional conversions at the same cost-per-acquisition. This is because our systems can better predict the incremental impact a specific ad will have on driving a conversion, and adjust bids accordingly to maximize your ROI” – Vidhya Srinivasan, VP/GM Buying, Analytics and Measurement at Google Ads.

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