I'll have to look into those commands but no, the survey is taken randomly. You only get the prompt when you're selected for that survey run.As far as I’m aware the sample size is all of steam. They don’t actually disclose the sample size but I’ve noticed I get a prompt asking me to participate every time I’ve upgraded a significant component within my rig.
However if you haven’t had that you can run one of the following commands in windows (windows key - R) to force it;
Edit: Ok, it looks like those commands work, but only once each.