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- Xref: sparky sci.energy:7171 talk.environment:5674
- Path: sparky!uunet!elroy.jpl.nasa.gov!nntp-server.caltech.edu!SOL1.GPS.CALTECH.EDU!CARL
- From: carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick)
- Newsgroups: sci.energy,talk.environment
- Subject: Re: Greenpeace press releases -- fact or fiction?
- Date: 23 Jan 1993 10:07:10 GMT
- Organization: HST Wide Field/Planetary Camera
- Lines: 37
- Distribution: world
- Message-ID: <1jr5ceINN16a@gap.caltech.edu>
- References: <C140AC.IuM@watserv1.uwaterloo.ca> <1993Jan19.180401.19851@mcshub.dcss.mcmaster.ca> <90464@ncratl.AtlantaGA.NCR.COM>,<1993Jan20.151948.20009@mcshub.dcss.mcmaster.ca>
- Reply-To: carl@SOL1.GPS.CALTECH.EDU
- NNTP-Posting-Host: sol1.gps.caltech.edu
-
- In article <1993Jan20.151948.20009@mcshub.dcss.mcmaster.ca>, whitlock@dcss.mcmaster.ca (Jeremy Whitlock) writes:
- >On the news last night: Greenpeace releases a commissioned report (from
- >someone in the U.S.) demonstrating that the chances of a meltdown accident
- >in a CANDU reactor are 1 in 17, which they point out are better odds than
- >the chance of throwing snake eyes with dice.
- >
- >To make the point, the Greenpeace spokesman shakes a pair of dice for 15
- >seconds while stating the above information (visual crutch telegraphed from
- >miles away), and then tosses the dice across the table.
-
- I take it, then, that Greenhype, true to form, neglected to mention the
- time-frame appropriate to their estimate.
-
- For the innumerates like Jym Dyer among you, if I get to pick the timeframe, I
- can get any probability I want for any event that's not 100% certain. Say
- we've got something that has a 10% chance of happening on any one trail. That
- means it's got a 19% chance of happening at least once in two trials, a 27%
- chance of happening at least once in three trials, a 34% chance of happening at
- least once in four trials, a 41% chance of happening at least once in 5 trials,
- and so forth. In other words, the chance of the event occurring at least once
- in N trials is 1-.1^N. So, if you pick a probability, P, we simply solve the
- equation:
- P = 1 - .1^N
- for N, getting N = -log(1-P) (logarithms to the base 10). Thus, if I get to
- pick the number of trials, I can get any probability I want. Of course, Jym's
- going to be falling all over himself excusing Greenhype for their latest piece
- of bullshit. Remember: According to Jym, *YOU* are too stupid to understand
- anything like this, so Greenhype *HAS* to "simplify" things in order for you to
- understand them.
- --------------------------------------------------------------------------------
- Carl J Lydick | INTERnet: CARL@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL
-
- Disclaimer: Hey, I understand VAXen and VMS. That's what I get paid for. My
- understanding of astronomy is purely at the amateur level (or below). So
- unless what I'm saying is directly related to VAX/VMS, don't hold me or my
- organization responsible for it. If it IS related to VAX/VMS, you can try to
- hold me responsible for it, but my organization had nothing to do with it.
-