[dabs]

Question for someone with a more theoretical background: The paper shows that the EMX learnability of some class of functions with respect to some set of probability distributions is undecidable. Does EMX learnability encompass all notions of learnability (or is it equivalent to other notions)? Conversely are there or could there be notions of learnability different from EMX that are not undecidable? Maybe I missed this in the paper but clarification would be appreciated.