A teacher of someone I know puts it like this: Let's say you have a fly in your room that you want to kill. You can do so by hitting it with a fly swatter or by shooting a canonball at it. Both are effective. Only one of them is efficient. Basically, effective means that it works, while efficient means that it works AND does not use a lot more resources than necessary.
It's a little weird sentence, but you can give it some sense. It means that she's a good model, not in the sense of wearing fancy clothes and running around on the catwalk, but as a simplified version of a principle.
For instance, let's say we're talking about the economics of a bakery and how the workers should behave in order to maximise revenue. We know of this real-life bakery with this real-life woman working in it whose style of work is close to this ideal behaviour, so we can say that she's an effective (good) model for this kind of economic theory.