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by sl8r 2287 days ago
Won't you possibly get some information about some passengers by doing this, if you know / can figure out the distribution of the random numbers?

E.g., say that the random numbers are uniformly distributed between -200 and 200. If somebody says a number like 425, then I know they weigh at least 225 pounds. And the probability they weigh more than 225 - k pounds is 1 - k/400.
1 comments
skrtskrt 2287 days ago
Yes absolutely, but you can just make the range wide enough to wash out the difference (like -2000 to 2000, summing to zero)

Then you would probably get more information from looking at the person thank you could from hearing a weight number that could be +/-2000 pounds

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XMPPwocky 2287 days ago
You could also do it modulo some number, I think?

Then knowing any individual number (weight + pad) mod n gives zero knowledge (I think. If all but one party reveal their pads, they can trivially determine the other's weight so it fails. Believe it to be secure if only 1 party is malicious, though. Cases for other numbers of bad actors are more complicated...)

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