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Re: "Representative sampling?"
Posted:
Nov 3, 2000 1:18 PM
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Once upon a time (up to 1925 or about), there was "representative sampling"
meaning, "creating a representation of the population in the sample" i.e.
quotas, The caricature is that to obtain the so-called representation, you
*have to* get those 5 middle-age out-of-work with post-secondary education
living in towns of less than 20000 people, otherwise ou don't have the
"true" representation. With Neyman's theory on disproportional allocation to
stratified random samples, "representative sampling" sort of faded away, at
least among (mathematical) statisticians dealing with survey sampling.
In the recent years, the only times I've heard/read "representative
sampling" were with reference to "the ability to obtain unbiased estimates
from the sample"; if memory serves, it was so defined by C.E.Särndal during
a conference. I have searched in more than 20 textbooks, never coming up
with any satisfying "modern" definition of "representative sampling".
Basically, (mathematical) statisticians have dropped the notion altogether.
When I hear it, I'll question the speaker (if I can) as to what he/she
actually means, and it more or less boils down to unbiasedness.
Jerry Dallal a écrit dans le message <3A02F5AA.476950C7@hnrc.tufts.edu>...
>Chris.Chambers@sci.monash.edu.au wrote:
>>
>> In article <hie30tsnuaqcr5nc1kb4ei83e1eadsovq3@4ax.com>,
>> wpilib@pitt.edu wrote:
>> > On Thu, 02 Nov 2000 17:44:08 GMT, Ross J. Micheals
>> > <dnxthx@my-deja.com> wrote:
>> >
>> > > Is there a statistical definition of "representative sampling?"
>> >
>> > No. It is more broadly *logical* than statistical. My notion right
>> > this minute is, it is most clearly defined by its negation. That is,
>> > if you avoid the traps of all potential non-representative-ness,
>> > then you may have representative samples.
>>
>> Surely the defining property of "representative sampling" is that it be
>> entirely random. Wouldn't any non-representative mistake violate some
>> notion of randomness?
>>
>
>Since it's not a technical term, it doesn't have a technical
>definition.
>The problem is that the "random" in random sample refers to the
>process that generated the sample whereas, as I hear it used in
>common parlance, the "representative" in representative sample seems
>to refer to the specific sample that was obtained as a result of the
>(possibly nonprobabilistic) sampling procedure.
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