Are you selfish? Yes or no, please. social experiment!
Everybody is selfish. A person cares more about a sore tooth in his own head than he cares about a famine in some foreign land that kills a million people. That is normal, and it is just part of staying alive.
But nobody wants to admit to being "selfish" because our culture attaches a bad meaning top the concept.
So what is your experiment? The results are perfectly predictable but not perfectly reliable.