Learning and Natural Language Processing

I am interested in finding provable methods for machine learning problems, applications in natural language processing, and intersections with computational economics and game theory.


Simple Semantic Feature Embeddings

Extending the success of word embeddings to more general semantic features has proven challenging and computationally difficult. We introduce a generic method based simple linear regression that can embed any language feature given examples of its usage in context. It is also very effective for one-shot and few-shot learning of word embeddings. 

[Paper] [Slides] [Dataset] [Code] [Corpus Data]

Compressed Sensing and Document Embeddings

A common application for low-dimensional document representations is text classification (e.g. via logistic regression/SVM). However, simple methods such as Bag-of-Words and Bag-of-n-Grams often outperform these distributed embeddings. We use the theory of compressed sensing to prove that, by preserving the information of the simpler methods, LSTM representations can do at least as well on linear text classification as Bag-of-n-Grams. In addition, we discover the surprising fact that given a document represented as a sum of pretrained word embeddings (e.g. GloVe/word2vec) one can recover the document's Bag-of-Words using basis pursuit (the noiseless version of the LASSO estimator).

[Paper] [Poster] [Embedding Code] [Recovery Code] [Word Vectors]

Joint with Sanjeev Arora, Nikunj Saunshi, and Kiran Vodrahalli

Self-Annotated Reddit Corpus (SARC)

Using the "/s" sarcasm annotation commonly used in the Reddit community we gather a large dataset for detecting sarcasm in online comments. The corpus has more than one million comments and can be used for exploratory purposes and to specify tasks for large-scale machine learning in both the balanced and unbalanced label setting.

[Paper] [Dataset] [Code]

Joint with Nikunj Saunshi and Kiran Vodrahalli.

Automated WordNet Construction Using Word Embeddings

We develop a method to automatically construct foreign-language WordNets using word embeddings and dictionary learning to augment machine translation. The English WordNet is a crucial tool in natural language processing that documents relations between words as well as other linguistic information. Our approach avoids the costly and time-consuming process of hand-constructing such a database for other languages while maintaining good precision and concept coverage.

[Paper] [Poster] [Code] [Dataset]

Joint with Andrej Risteski, Christiane Fellbaum, and Sanjeev Arora.