As as already been pointed out it's not correct. Your EV, although positive, is +$0.50 cents, not +$1. Another nitpick: in Poker you'd more see the $1 as the p

As as already been pointed out it's not correct. Your EV, although positive, is +$0.50 cents, not +$1. Another nitpick: in Poker you'd more see the $1 as the price to participate, and $3 as the gain (because in Poker what you put in the pot is considered "not yours" anymore). So the math is ($3 * 0.5 -$1), which also gives 50 cents and which, arguably, is more logical (but really it's a minor nitpick). As the problem is presented in the article you wouldn't see it that way but then Poker is mentioned so...