Dennis and All -- Dennis writes...
> thus, they do know something about phone subscribers ... > that, the average > joe or mary does not But all the average joe or mary has to do is get a phone book and look up the numbers. If they aren't there, they are unlisted. So, except for time I still don't see that Gallup has any different sampling capability than I -- I can know their Listed/Unlisted measure just as well as Gallup. -- Chris Chris Olsen George Washington High School 2205 Forest Drive SE Cedar Rapids, IA (319)-398-2161 > -----Original Message----- > From: dennis roberts [mailto:[EMAIL PROTECTED]] > Sent: Tuesday, December 03, 2002 3:40 PM > To: Olsen Chris; Jill Binker; AP Statistics; > [EMAIL PROTECTED] > Subject: Re: Gallup organization on polling methods > > > random sampling has nothing to do with any particular person > being selected > ... but, rather, in the LONG run, making sure that sampleS will be > representative of the target population ....whether i ever > get into any > random sample has no import > > what is the target population here? all people who have > telephones? all > people who have telephones that are listed ... ? unlisted ? > all people with > and without telephones ... with those having telephones being > listed? or, > including UNlisted? > > if gallup uses a method that uses ONLY random sampling of all > telephone > subscribers (residential) ... then in the LONG run ... samples would > reflect that ... but, when they do sampling ... it is a SHORT > RUN deal ... > so, to insure that all of the important categories are > included ... they > would have to know aHEAD of time who fits into which category ... > > thus ... > > i will make the assumption that gallup CAN (if it desires) > separate listed > numbers from UNlisted numbers ... does anyone have any specific > documentation that says otherwise? > > that is ... i assume that gallup could (if they knew that > about 2% of all > #s were unlisted) ... ask the "computer" (or dictate to the > group that does > the selection) to stratify their sample so that about 2% are from the > unlisted category ... thus guaranteeing some UNlisted > representation in > their sample ... on the spot ... in the SHORT RUN > > does anyone know if that is true or not? > > if it were true, which i assume is the case, then ... the > rules are not the > same for sampling ... you and i have no way of assuring that UNlisted > numbers could be found if we wanted to do a poll ... but, gallup could > > it's not the ability to contact ME specifically (if my # is > unlisted), it > is the ability to absolutely know that some of their sample > WILL be from > the UNlisted category ... > > no one else who wants to do telephone sampling ... has any > way to guarantee > that > > thus, they do know something about phone subscribers ... > that, the average > joe or mary does not > > > > . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
