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statistics the study of how to collect, organize, analyze, and interpret numerical
information
population entire group of people or objects about which we want information
sample subset of the population for which we gather data
voluntary sample bias
convenience sample bias
census sample consisting of the whole population. (expensive, time consuming, never
perfect)
nominal data only put into categories (hair color)
ordinal we can determine whether one unit has more of the property being measured
than another (football ranking)
interval we can tell how much more of the property one unit has than another
(temperature)
ratio we can tell the actual amount of the property each unit possesses (has a 0, weight
in kg)
simple random sample each subset of n units from the population has the same chance
of being selected
stratified sampling divide population into strata and take a simple random sample from
each stratum
systematic sampling sample at regular intervals in data stream
cluster sampling divide population into strata, take random sample of strata, do census
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This test prep was uploaded on 04/01/2008 for the course STAT 3604 taught by Professor Rsschulman during the Fall '06 term at Virginia Tech.
 Fall '06
 RSSchulman
 Statistics

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