Fundamentals of Statistics contains material of various lectures and courses of H. Lohninger on statistics, data analysis and chemometrics......click here for more. |
Home Basic Concepts Definition of basic terms Samples | |||||
See also: population, sampling distributions, Venn diagram | |||||
SamplesA sample is a subset
of the population, a set of n states of
a random variable. Normally, statistical
data are samples, however, most statistical techniques have been developed
for populations. This gives rise to several aspects which have to be considered
when working with statistical data:
(1) the equations derived for populations do not hold for samples if the sample space is small. In many cases there are special formulas for samples, which should be applied whenever you need to calculate a statistical descriptor for the sample. For example, the formula to calculate the variance is different for samples and for populations: |
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