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A comment on iPhone X. Parent comment

Re:iPhone X by Grustaf on Tuesday September 12, 2017 @04:05PM (#15231834)
The difference is that if two people in e.g. a class have the same birthday then there will be a day when those two have birthdays, whereas if two people in the same auditorium have the same code, or face, then that has no implications. There is no process where all faces are cycled through and applied to all phones or similar.

So regardless of how many people in a room, or a country, have the same face you still need to bring your one phone up to 1 million people to unlock it.

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Re:iPhone X by nathancahill on Tuesday September 12, 2017 @06:07PM (#15233348)
More succinctly, there's only 365 possible birthdays while there's 1,000,000 possible "faces".
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Re:iPhone X by Nition on Tuesday September 12, 2017 @06:23PM (#15233488)
I don't think that's what Grustaf is saying.

The thing is if two of you have the same birthday then it falls on the same day . But if two of you have the same face, that doesn't mean you have to use the same phone. So unlike the birthday paradox where your birthdays "clash", you'd still have to try everyone's face on everyone's phone.

An actual Birthday Paradox equivalent would be if you had 1,000,000 phones and the 1,179 people in the auditorium, and you assigned people to a phone based on their face recognition ID. Then you would get your high chance that not everyone would get a unique phone.

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Re:iPhone X by benchaney on Tuesday September 12, 2017 @06:12PM (#15233396)
You missed the point. GP is describing a qualitative difference, not just a quantitative one.
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