Neural Episodic Control
arxiv.org
arxiv.org
I reckon they _don't_ train the CNN, rather, they use it as pre-trained from DQN or something. In that case, no wonder it learns faster.
Without this I'd be quite skeptical of these claims but now I'm wishing for analysis from someone better qualified than I am.
If you mean they are returning to tabular Q-learning, then yes, sort of. They still use function approximation (as required; tabular Q-learning stands no chance of generalising across states), but their function kind of looks like a table look up. A look up of the 50 closest values to some computed key though.
It would be totally uninteresting to compare this with tabular Q-learning though.