Ever wonder why election polls keep missing? It's not the math. The math is always fine.
It's that the kind of person who picks up an unknown number, stays on the line, and answers twenty minutes of questions about politics is a fundamentally different animal than the kind of person who doesn't. A bigger sample doesn't fix that. A better sample does.

I'd trust 30 people chosen truly at random over 500 who volunteered. That's not a hunch. That's how sampling actually works.

Four reasons "statistically significant" doesn't mean what you think.