Ideea ca un numar mic de unitati alese la intamplare (monstra) dintr-o populatie (universul) va tinde sa aiba aceleassi caracteristici, si in aceleasi proportii, ca populatia ca intreg
the idea that a small number of randomly chosen units (the sample) of a total population (the universe) will tend to have the same characteristics, and in the same proportion, as the population as a whole.
