If you're not deeply trained in statistics or math, how do you know a good marketing analytics model from a poor one? It's more than an idle question. The difference could mean meeting your goals or not, or having to go back to beg for more marketing dollars before the year is out. It could mean spending way too much on a media channel that's beginning to suffer fatigue and not nearly enough on a fresh media channel that could rocket your sales. It also could mean you over- or understaffed call centers because you weren't able to accurately predict customers' responses to your calls to action.