A different (and better?) type of hierarchy for a mixture of experts
		• Instead of just using a hierarchy of gating nets, also use a hierarchy of experts. • Learn the whole system by greedy divide-and-conquer. – Start by learning a single expert. – Then make two slightly different copies of the expert, and use EM to rapidly fit an MoE with one gating network and two experts. – Now split each of these two experts. Use the previous gating network as the initial top-level gating net and add two new gating nets (with zero weights) at the next level down.