They don’t understand probability

  • Kazumara@discuss.tchncs.de
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    2 days ago

    So they only counted those who did 500 rides a year? Or they counted 50’000’000 rides as a proxy for 100’000 subway users?

    • elderorb@feddit.nl
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      2 days ago

      I am guessing they took the average homicide rate per ride in the metro, and used those rates to create the per capita rate assuming they take 500 rides a year.

      • Kazumara@discuss.tchncs.de
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        1 day ago

        Oh yeah I can see it, that would make sense! Thanks!

        Since a lot of tickets will be bought anonymously you can’t easily count unique users of the subway system, so the raw data probably consisted of numbers of homicides, and number of rides taken by all customers combined.

        But the rate between those wouldn’t fit the per person risk they want to be comparing. So to calculate a risk to a person they must have assumed a realistic case towards the higher end of ridership, that is, a commuter commuting 5 days a week for 50 weeks a year, to work and back, that would give the 500 rides number.