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- From: c23st@kocrsv01.delcoelect.com (Spiros Triantafyllopoulos)
- Newsgroups: rec.autos
- Subject: Re: yet another consumer reports article (Re: Before Buying Japanese.)
- Message-ID: <1993Jan26.195735.15152@kocrsv01.delcoelect.com>
- Date: 26 Jan 93 19:57:35 GMT
- References: <1993Jan22.181330.2179@kocrsv01.delcoelect.com> <1993Jan25.174221.11394@magnus.acs.ohio-state.edu> <1993Jan25.182614.5898@kocrsv01.delcoelect.com> <1993Jan26.152710.2253@magnus.acs.ohio-state.edu>
- Sender: news@kocrsv01.delcoelect.com (Usenet News Account)
- Distribution: na
- Organization: Delco Electronics Corp.
- Lines: 108
-
- In article <1993Jan26.152710.2253@magnus.acs.ohio-state.edu> jnielsen@magnus.acs.ohio-state.edu (John F Nielsen) writes:
-
- [stuff regarding validity of CR stats deleted]
-
- > What you are doing it taking the community of people who drink Folgers,
- > Maxwell House, and Hills Bros and comparing them to each other.
- > In other words, you are already looking at people with type A personality
-
- But, we have no idea *how much coffee* each of our type A drinkers is
- drinking; or, if they're taking it with donuts, muffins, Cuban cigars,
- or Marlboros. Or whether they drink 5 cups in one shot or spread out
- over the day. Or how much ground coffee they use per mug; Or the
- drinkers' predisposition to heart disease, diabetes, etc.
-
- Just as we don't know if some cars were babied while some cars were
- abused (intentionally or not), driven in Florida/Minessota, etc.
-
- > In this case, you are already looking at people who want to respond
- > to the CU questionaire.
-
- Notice 'want to respond'. Studies have proven that dissatisfied customers
- 'want to' respond much more than satisfied customers 'want to'. That
- would mean that for (say) every K car with a black donut there *could*
- be 10 K cars with red donuts who did not respond. So much for donuts.
-
- > >There is also the issue of sample size; how many CR readers drive K-cars
- > >vs. Accords? and out of these K-car-CR-readers, how many respond vs
- > >how many Accord-CR-readers? Out of how many? and in what proportions?
- >
- > First off, most people do not buy cars because they think it is
- > going to break down. And, it is not that hard to know when your car
- > broke down. And, most people are not pleased that their car breaks
- > down.
-
- While it is not hard to know that the car broke down, it can be hard
- to the non-car enthusiasts to judge what component failed, and,
- whether it failed because of abuse/misuse or because of normal wear
- and tear. I.e. for a Honda owner, a brake job every 30,000 miles is
- routine. For MY Honda it ain't. (I don't consider it routine). So
- what does get classified as a breakdown? Do people understand the
- significance of preventive maintenance? Do they INCLUDE preventive
- maintenance in their reports to CR? How about routine items (clutch,
- struts, mufflers, ...).
-
- We also can't know whether a minor problem escalated into a major
- one. It takes only a few basket cases to screw up an otherwise
- good score in any case; given a LARGE sample and with proper
- analysis methods it will smooth itself out; But we have no idea
- of CR's sample size (c'me on, after 10 years of blacklisting
- certain cars, CR still finds readers driving them.... :-),
- and/or analysis methods. Hence, meaningless.
-
- > An annoying problem is an annoying problem. I don't think it
- > signifiantly matters *what* car you are driving. If the car has
- > to be in the shop for a week, you'll be annoyed and remember it.
- > Unless you assume people are morons.
-
- No, people are not morons. Sometimes people choose to be upset by
- MINOR flaws... And I am glad you brought the shop factor in; do
- we judge car brands by COMPETENCE of repairs? Sounds like we should
- account for that also. I.e. if my car breaks down and it takes a
- week for Dumbo's Import Cars and Farm Equipment to figure out what's
- wrong with it, while for the same problem Smart Alek's Honda fixes
- it in an hour, does *my* confidence in the car change? you bet it
- does.
-
- This also brings in YET another factor that is not shown in CR stats,
- that is, the WEIGHT of the repairs. Weight means that different
- types of defects/breakdowns are considered different. Do we brand
- a stuck power window switch the same as a rusted thru fender after
- one year? Both are 'BODY problems'...
-
- > >It is simply for the same reason that call-in audience polls are NOT
- > >accurate. CR or anyone else has no way of controlling the response
- > >rate, or of mapping the responses back to a correct population.
- >
- > It is not necessary to map it back to the population. In other words,
- > you don't look at it to determine what the failure rate of the
- > population is since it is probably skewed by the readership. You look
- > at it to compare if the Ford Crown Vic is more reliable than the Chevy
- > Caprice.
-
- But, if we have no idea over sample sizes (how many of each?), use
- (how many Crown Vics are driven by 70 year olds in Florida vs. how
- many Caprices are used to tow boats in Wisconsin), and a lot of other
- factors (even things like dealer service expectations/capabilities),
- all the CR studies say is that "some of our readers with Caprices who
- bothered to respond found this and this with their car while some of
- our readers with Crown Vics who bothered to respond found that and
- that". Again, with large sample sizes these things smooth out somehow
- but we *don't* have their sample sizes (or the sampling method :-)).
-
- > So, as I said, for their purpose it is not necessary.
-
- But it ain't accurate, either. And while sophisticated people can
- differentiate between accurate statistics and meaningless anecdotal
- evidence, not everybody can.
-
- And that's the whole point. All some people do is look at CR (or any
- other publication), see a couple of pictures of authoritative-looking
- folks in white lab coats and sophisticated instrumentation, and it
- might as well have been G*d delivering The Commandments to Moses...
-
- Spiros
- --
- Spiros Triantafyllopoulos c23st@kocrsv01.delcoelect.com
- Software Technology, Delco Electronics (317) 451-0815
- GM Hughes Electronics, Kokomo, IN 46904 [A Different Kind of Disclaimer]
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