Subject: Re: Nielsons (was:Re: Secret Diary sales) From: hildreth@cg-atla.UUCP (Lon Hildreth) Date: 1990-11-02, 10:38 Newsgroups: alt.tv.twin-peaks In article <8402@darkstar.ucsc.edu> unknown@ucscb.UCSC.EDU (The Unknown User) writes: > > > >In article <1990Oct29.065308.4866@agate.berkeley.edu> physi-bs@garnet.berkeley.edu (Marc D. Peters) writes: >> >>Reason #2: There are very, very few 'Nielsen families' out there. Something >> >>like <.01% of the viewing audience is one. Statistical variations are possible. > > > > Well, I don't have the statistical background to go into this, but I > >do know that seemingly -TINY- samples can give very very very accurate > >representations as a whole.. Someone else may want to elaborate on this, but > >I believe they do use a very significantly large sample for what they're trying > >to measure. I took a statistics course back in high school (gee, that would have been 14-15 years ago). My memory may be a little hazy on the specifics but I recall our teacher talking about the Nielson ratings. At the time they had about 1200 sampled households. I think they've increased their sample size since then. Anyway, there are statistical methods (which I've long since forgotten) to show you the accuracy of your sample. As I recall, there was nearly a 100% level of confidence that a sample size of 1200 would be at least 94% accurate. I think it there was a 95% level of confidence that it would be at least 97% or 98% accurate. It was enough to convince me that the ratings were pretty accurate even though they often did not match what I watched. -- Lon Hildreth ...!{decvax,uunet,samsung}!cg-atla!hildreth Agfa Compugraphic or hildreth@cg-atla.agfa.com Wilmington, MA A Cub fan, but not a Bud man.

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