A measurement of Perplexity's grounding finds three sites publishing 215,128 machine-generated buying guides among its most-cited sources

Sources: primary, discussion
Summary: The report examines what Perplexity cites when it recommends products, and states that three sites among its most-cited sources publish 215,128 machine-generated buying guides between them. The authors state that two of the three name their homepage with the HTML page title Facts and Grounding Page, which is the retrieval step named in the page's own metadata. The report states its own limits: one snapshot, Perplexity only, categories of the authors' own construction, and no test of whether removing those sources changes the recommendations, and it publishes its dataset under CC BY 4.0.
Why it matters: The measurement is of what the evidence base under a grounded answer is made of rather than of whether the answer is right, which is a failure surface no model benchmark covers.
Follow-up: Track whether the dataset is reproduced independently or whether Perplexity states a position on the named sources.