That probably varies a lot by region and neighborhood. My neighbors and I don't usually stop at our stop sign. But the sight lines are good and none of us drive faster than 15 mph, so formally stopping just because there is a sign is not worth much. If someone is walking or riding their bike, we stop for them whether there's a stop sign or not. We did have a neighbor once who tended to speed, but peer pressure turns out to be pretty effective, he drives as slow as the rest of us now.