Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!brutus.cs.uiuc.edu!wuarchive!swbatl!texbell!vector!telecom-gateway From: sje!tom@pdx.mentor.com (Tom Ace) Newsgroups: comp.dcom.telecom Subject: Re: Divestiture, Business and the General Public Message-ID: Date: 22 Aug 89 18:40:14 GMT Sender: news@vector.Dallas.TX.US Lines: 28 Approved: telecom-request@vector.dallas.tx.us X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@vector.dallas.tx.us X-TELECOM-Digest: volume 9, issue 318, message 10 of 12 John DeArmond , discussing air travel, said: >And as anyone who has looked below the surface of this subject knows, >"deaths per passenger mile" is a completely bogus measurment which >does not represent the true safety condition of modern air travel. As >a larger and larger proportion of a carrier's fleet becomes high capacity >jumbo-jets, the DPPM magically goes down even while the crash rate is up. Let me see if I get your reasoning right. They pack the same number of people on fewer planes, so fewer crashes happen (fewer planes to crash), and voila--the DPPM goes down. Isn't it essentially a wash, though, because if there are now more people per plane on the average, each crash is likely to result in more fatalities? DPPM may not measure what _you_ want to know, but it is hardly a "completely bogus measurement". If I want to know the odds of my dying when I fly 1900 miles, I can calculate that from a DPPM figure. I cannot calculate that from the "deaths per vehicle mile" figure which you say is more useful. Each metric has its particular applications. (This IS the Telecom digest, isn't it?) Tom Ace tom@sje.mentor.com ...!mntgfx!sje!tom [Moderator's Note: Yes, its TELECOM, and we have probably exhausted this topic for now, at least in this forum. PT]