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Path: utzoo!watmath!clyde!burl!ulysses!allegra!alice!jj
From: jj@alice.UUCP
Newsgroups: net.politics
Subject: Subway sheep, facts/statistics
Message-ID: <3441@alice.UUCP>
Date: Wed, 6-Mar-85 14:49:21 EST
Article-I.D.: alice.3441
Posted: Wed Mar  6 14:49:21 1985
Date-Received: Thu, 7-Mar-85 05:47:45 EST
Organization: New Jersey State Farm for the Terminally Bewildered
Lines: 40


Tim Sevener points out that the chance of being killed  in the
NY subway is 1 in 142,000,000 rides.  That is an impressive number,
but it really doesn't have anything much to do with the threat
that an individual faces on the subway.  First, let's assume that
a resident of one of the poorer areas has to use the subway to
go to/from work every day.  That's roughly (allowing for weekend
use, etc) 700 trips per year.  This  means that the chance of
not being murdered changes from .999999993 to the 700th power
of that number, approximately .999995, making the chance of
being murdered in a year, assuming that the 1/142000000 number
exactly applies, about 1 in 202634 or so, which is a big difference.
(Note that one can only be murdered once, so the appropriate statistic
is the chance of survival of each ride, NOT the chance of death!)

Now, then, let's assume that the person in question has to ride from
an EL stating somewhere in Bronx/Brooklyn that is in a BAD area,
and that they have to ride to work in the afternoon rush hour (as
safe as any time) and BACK from work at 2:00 AM, after working second
shift, which is the only work they can get.  I would personally
assume that it si much more dangerous  on the subway at
2AM, given my personal experience, at least.  

Let's say it's ten times as dangerous then, (just a guess, NO
hard figures, but I suspect it's an underestimate!) so we
have 350 trips at one risk, yeilding a chance of safety of .999997532,
and 250 trips, yeilding a chance of safety of safety of .999975349,
or a chance of safety in tot of a*b of .999972881, or one chance
in 36875 of being killed each year.     That's not nearly as good
odds as one would like.

These numbers, of course, do not cover any sort of non-fatal
outcome.

Anyone want to compare this risk to driving an auto, etc?
-- 
FESTINA LENTE

"...rice is nice, that's what they say..."
(allegra,harpo,ulysses)!alice!jj