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by ehnto 1832 days ago
When they've learned that your base heart rate is ~70bpm and when you get shown a puppy your heart rate excites by 20bpm they can guess that you like puppies. They could be wrong, and it could be that you're actually terrified of puppies, but they'd be safe in assuming that you're a big fan of them and so they add "Enjoys puppies" to their advertising profile of you.