Here's a baffling example which shows that Google's algorithms aren't always so smart. When you search for [Robert Greene], Google shows some information about an American author who was born in 1959 and died in... 1592. Google confused Robert Greene, the American author, with Robert Greene, a 16th-century English writer. The American author is alive and still writes books.
The good news is that you can tell Google when you found an error like this by clicking "Feedback/More info" and then "Wrong?" next to the information that's incorrect. Still, you'd expect Google to check if the date of death is more recent than the date of birth.
Update (November 28): It took a few days, but Google fixed this issue.
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Google and Brandy: a sober mistake
What's the right answer?
{ Thanks, Roie Ambulo. }