“Pretty much everyone knows we’re using clicks in rankings. That’s the debate: ‘Why are you trying to obscure this issue if everyone knows?’”
That quote comes from Eric Lehman, a former 17-year employee of Google who worked as a software engineer on search quality and ranking. He left Google in November.
Lehman testified last Wednesday as part of the ongoing U.S. vs. Google antitrust trial.
If you haven’t heard this quote yet, expect to hear it. A lot.
But. That’s not all Lehman had to say. Google’s machine learning systems BERT and MUM are becoming more important than user data, he said.
- “In one direction, it’s better to have more user data, but new technology and later systems can use less user data. It’s changing pretty fast,” Lehman said, as reported by Law360.
Lehman believes Google will rely more heavily on machine learning to evaluate text than user data, according to an email Lehman wrote in 2018, as reported by Fortune:
- “Huge amounts of user feedback can be largely replaced by unsupervised learning of raw text,” he wrote.
User vs. training data. There was also a confusion around “user data” vs. training data” when it came to BERT. Big Tech on Trial reported:
Sensitive Topics. Lehman was also asked by DOJ attorney Erin Murdock-Park about a slide from one of his slide decks on “Sensitive Topics” that instructed employees to “not discuss the use of clicks in search…”
According to reporting from Big Tech on Trial (via X), Lehman said “we try to avoid confirming that we use user data in the ranking of search results.”
The reporter X post says “I didn’t get great notes on this, but I think the reason had something to do with not wanting people to think that SEO could be used to manipulate search results.”
Google = liars? Since discovering this testimony, SEOs have been quick to use Lehman’s quotes as definitive proof that Google has been lying about using clicks or click-through rate for all of its 25 years.
The question of whether Google uses clicks was the first question asked last week during an AMA with Google’s Gary Illyes at Pubcon Pro in Austin. Illyes answer was “technically, yes,” because Google uses historical search data for its machine-learning algorithm RankBrain.
Technically yes, translated from Googler speak, means yes. RankBrain was trained on user search data.
We know this because Illyes already told us this in I am Gary Illyes, Google’s Chief of Sunshine and Happiness & trends analyst. AMA on Reddit in 2018. He said RankBrain:
- “uses historical search data to predict what would a user most likely click on for a previously unseen query.”
RankBrain was used for all searches, impacting “lots” of them, starting in 2016.
So how is Google Search using clicks? The fact that Google tracks every click in Search does not mean clicks are necessarily used as a direct ranking factor. In other words, if site A gets 100 clicks and site B gets 101 clicks, then site B automatically jumps up to Position 1.
Much like how Google employs people (quality raters) to rate the quality of its search results, Google has said they use click data for evaluating experiments and personalization.
In a 2017 interview, Illyes said clicks are a “very noisy signal”:
And here’s an exchange between Illyes and Search Engine Land co-founder Danny Sullivan (now at Google) from 2015:
Why we care. Does Google use clicks? Clearly, yes. But again, probably not as a direct ranking signal (though admittedly I can’t say that with 100% certainty as I don’t work at Google or have access to the algorithm). I know clicks are noisy and easy to manipulate. And for many sites/queries, there simply wouldn’t be enough data to evaluate to make it a useful ranking signal for Google.
Dig deeper. The biggest mystery of Google’s algorithm: Everything ever said about clicks, CTR and bounce rate
Additional reading. In Google Patents Click-Through User Feedback on Search Results to Improve Rankings (2015), Bill Slawski described a patent explaining how Google might rank pages based on user feedback (clicks) in response to rankings for those pages.