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Random Sampling |
Random Sampling:
To make valid nontrivial generalizations
from samples of a population.
samples must be obtained by a scheme to insure:
1. Relevant Characteristics: Sample must bear
a know relationship to the
corresponding characteristics of the population
2. Generalizations may be drawn from samples in accordance with
given "book of rules" whose validity rest on the
Mathematical theory of probability
For a sample to meet the above criteria, it must be obtained through
some type of random selection
Randomness:
That property that requires
each individual in a population having
an equal chance of being selected
In practice random sampling is a difficult task