It tells you something about the group as a whole (not any individual member of the group) IF you are able to gather enough data to have a representative sample

It tells you something about the group as a whole (not any individual member of the group) IF you are able to gather enough data to have a representative sample of the population. If you were only able to get the net worth of 20% of the people in the above room, the vast majority of the time you'd conclude that the average net worth of the room is $0. There are some 3.5 billion women on the planet. Do you think you've reviewed the programming work of enough of them to constitute a representative sample? > You have to work with what you know Yes, what I'm pointing out is that you don't have enough information to claim to know anything.