djcthe $4.99 sub gets split down the middle, half to twitch half to the streamer
iirc it's $0.02 cents per ad view and you get paid out @ $100
i'm pretty damn sure it's not $0.02 viewer per ad view as that is way too high.
[edit] did some research
http://support.twitch.tv/discussion/1441/how-much-does-twitch-pay-out
$5/1000 views per hour = $10 / 2000 views per hour.
so if you're getting 2,000 viewers you're making $10/hour which is around minimum wage.
$10/2000 views = half a cent per viewer per hour ($0.005) and your calculation is four times that.