<p>Expected value can play around with your mind a bit.</p>
<p>For example, if you had the choice of taking $100,000 now or going for a 1/2 chance at $1,000,000, which would you choose? What if it was $100,000 now or a 1/2 chance at $280,000? $100,000 now or 1/2 chance at $201,000?</p>