in statistics, a random sampling or sample
Random selection is how you draw the sample of people for your study from a population.
This is no more than a random selection; his portraits and drawings of fair women are numbered by the hundred.
Did his random selection of keys indicate something to it, something about his mental powers or emotions or—what?
One cannot make a random selection from his pictures and pronounce upon the qualities of his art.
I've had follow-ups on a random selection of her cases—standard practice for a newcomer.
Not exhaustively, of course, just a random selection of say ten and then report back to one another.