1) The character tri-gram LSTM seems a little unmotivated. Did the authors try other character n-grams as well? As a reviewer, I can guess that character tri-grams roughly correspond to morphemes, especially in Semitic languages, but what made the authors report results for 3-grams as opposed to 2- or 4-? In addition, there are roughly 26^3=17576 possible distinct trigrams in the Latin lower-case alphabet, which is enough to almost constitute a word embedding table. Did the authors only consider observed trigrams? How many distinct observed trigrams were there?
2) I don't think you can meaningfully claim to be examining the effectiveness of character-level models on root-and-pattern morphology if your dataset is unvocalised and thus doesn't have the 'pattern' bit of 'root-and-pattern'. I appreciate that finding transcribed Arabic and Hebrew with vowels may be challenging, but it's half of the typology.
3) Reduplication seems to be a different kind of phenomenon to the other three, which are more strictly morphological typologies. Indonesian and Malay also exhibit various word affixes, which can be used on top of reduplication, which is a more lexical process. I'm not sure splitting it out from the other linguistic typologies is justified.
- General Discussion: 1) The paper was structured very clearly and was very easy to read.
2) I'm a bit puzzled about why the authors chose to use 200 dimensional character embeddings. Once the dimensionality of the embedding is greater than the size of the vocabulary (here the number of characters in the alphabet), surely you're not getting anything extra?
------------------------------- Having read the author response, my opinions have altered little. I still think the same strengths and weakness that I have already discussed hold.
1) The character tri-gram LSTM seems a little unmotivated. Did the authors try other character n-grams as well? As a reviewer, I can guess that character tri-grams roughly correspond to morphemes, especially in Semitic languages, but what made the authors report results for 3-grams as opposed to 2- or 4-? In addition, there are roughly 26^3=17576 possible distinct trigrams in the Latin lower-case alphabet, which is enough to almost constitute a word embedding table. Did the authors only consider observed trigrams? How many distinct observed trigrams were there?