Task: Language Identification
Input (Spanish, English): Thank you for an interesting read.   To my knowledge, very few papers have looked at transfer learning with **no** target domain data (the authors called this task as "extrapolation"). This paper clearly shows that the knowledge of the underlying system dynamics is crucial in this case. The experiments clearly showed the promising potential of the proposed EQL model. I think EQL is very interesting also from the perspective of interpretability, which is crucial for data analysis in scientific domains.  Quesions and comments:  1. Multiplication units. By the universal approximation theorem, multiplication can also be represented by a neural network in the usual sense. I agree with the authors' explanation of interpolation and extrapolation, but I still don't quite understand why multiplication unit is crucial here. I guess is it because this representation generalises better when training data is not that representative for the future?  2. Fitting an EQL vs. fitting a polynomial. It seems to me that the number of layers in EQL has some connections to the degree of the polynomial. Assume we know the underlying dynamics we want to learn can be represented by a polynomial. Then what's the difference between fitting a polynomial (with model selection techniques to determine the degree) and fitting an EQL (with model selection techniques to determine the number of layers)? Also your experiments showed that the selection of basis functions (specific to the underlying dynamics you want to learn) is crucial for the performance. This means you need to have some prior knowledge on the form of the equation anyway!  3. Ben-David et al. 2010 has presented some error bounds for the hypothesis that is trained on source data but tested on the target data. I wonder if your EQL model can achieve better error bounds?  4. Can you comment on the comparison of your method to those who modelled the extrapolation data with **uncertainty**?
Output (English): en