representativeness—the extent to which areas selected for inclusion in the reserve system are capable of reflecting the known biological diversity and ecological patterns and processes of the ecological community or ecosystem concerned.
(see also textbook glossary) A heuristic in which a person chooses the event that seems to be most representative of the population or process.
A sample is representative when it accurately reflects the population it is drawn from. When drawan at random, a very large sample can be assumed to be representative, but a small sample may be unrepresentative. To guard against unrepresentativeness, a sample can be stratified, or a maximum variation ample can be drawn.
How accurately the sample represents the entire population (all people with the designated characteristics) (Fortune, 1999)
The degree to which a sample is, or samples are, characteristic of the whole medium, exposure, or dose for which the samples are being used to make inferences.
The property of a sample (set of observations) that they are characteristic of the system from which they are a sample or which they are intended to represent, and thus appropriate to use as the basis for making inferences. A representative sample is one that is free of unacceptably large bias with respect to a particular data quality objective.
(in relation to a Protected Area System) The principle that the system samples known biological and biophysical diversity and other values.