Caglar Gulcehre


2017

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Machine Comprehension by Text-to-Text Neural Question Generation
Xingdi Yuan | Tong Wang | Caglar Gulcehre | Alessandro Sordoni | Philip Bachman | Saizheng Zhang | Sandeep Subramanian | Adam Trischler
Proceedings of the 2nd Workshop on Representation Learning for NLP

We propose a recurrent neural model that generates natural-language questions from documents, conditioned on answers. We show how to train the model using a combination of supervised and reinforcement learning. After teacher forcing for standard maximum likelihood training, we fine-tune the model using policy gradient techniques to maximize several rewards that measure question quality. Most notably, one of these rewards is the performance of a question-answering system. We motivate question generation as a means to improve the performance of question answering systems. Our model is trained and evaluated on the recent question-answering dataset SQuAD.

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Plan, Attend, Generate: Character-Level Neural Machine Translation with Planning
Caglar Gulcehre | Francis Dutil | Adam Trischler | Yoshua Bengio
Proceedings of the 2nd Workshop on Representation Learning for NLP

We investigate the integration of a planning mechanism into an encoder-decoder architecture with attention. We develop a model that can plan ahead when it computes alignments between the source and target sequences not only for a single time-step but for the next k time-steps as well by constructing a matrix of proposed future alignments and a commitment vector that governs whether to follow or recompute the plan. This mechanism is inspired by strategic attentive reader and writer (STRAW) model, a recent neural architecture for planning with hierarchical reinforcement learning that can also learn higher level temporal abstractions. Our proposed model is end-to-end trainable with differentiable operations. We show that our model outperforms strong baselines on character-level translation task from WMT’15 with fewer parameters and computes alignments that are qualitatively intuitive.

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Memory Augmented Neural Networks for Natural Language Processing
Caglar Gulcehre | Sarath Chandar
Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing: Tutorial Abstracts

Designing of general-purpose learning algorithms is a long-standing goal of artificial intelligence. A general purpose AI agent should be able to have a memory that it can store and retrieve information from. Despite the success of deep learning in particular with the introduction of LSTMs and GRUs to this area, there are still a set of complex tasks that can be challenging for conventional neural networks. Those tasks often require a neural network to be equipped with an explicit, external memory in which a larger, potentially unbounded, set of facts need to be stored. They include but are not limited to, reasoning, planning, episodic question-answering and learning compact algorithms. Recently two promising approaches based on neural networks to this type of tasks have been proposed: Memory Networks and Neural Turing Machines.In this tutorial, we will give an overview of this new paradigm of “neural networks with memory”. We will present a unified architecture for Memory Augmented Neural Networks (MANN) and discuss the ways in which one can address the external memory and hence read/write from it. Then we will introduce Neural Turing Machines and Memory Networks as specific instantiations of this general architecture. In the second half of the tutorial, we will focus on recent advances in MANN which focus on the following questions: How can we read/write from an extremely large memory in a scalable way? How can we design efficient non-linear addressing schemes? How can we do efficient reasoning using large scale memory and an episodic memory? The answer to any one of these questions introduces a variant of MANN. We will conclude the tutorial with several open challenges in MANN and its applications to NLP.We will introduce several applications of MANN in NLP throughout the tutorial. Few examples include language modeling, question answering, visual question answering, and dialogue systems.For updated information and material, please refer to our tutorial website: https://sites.google.com/view/mann-emnlp2017/.

2016

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Pointing the Unknown Words
Caglar Gulcehre | Sungjin Ahn | Ramesh Nallapati | Bowen Zhou | Yoshua Bengio
Proceedings of the 54th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

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Generating Factoid Questions With Recurrent Neural Networks: The 30M Factoid Question-Answer Corpus
Iulian Vlad Serban | Alberto García-Durán | Caglar Gulcehre | Sungjin Ahn | Sarath Chandar | Aaron Courville | Yoshua Bengio
Proceedings of the 54th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

2014

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Learning Phrase Representations using RNN Encoder–Decoder for Statistical Machine Translation
Kyunghyun Cho | Bart van Merriënboer | Caglar Gulcehre | Dzmitry Bahdanau | Fethi Bougares | Holger Schwenk | Yoshua Bengio
Proceedings of the 2014 Conference on Empirical Methods in Natural Language Processing (EMNLP)