DLSRL

Background

This repository contains a partial implementation of the semantic role labeling model reported in He et al. (2017) using Python 3.5 and tensorflow 2.0.

The paper describing the original implementation can be found here:

Deep Semantic Role Labeling: What works and what's next

The code is for research purpose only. The goal of this research project is to model early language acquisition. Specifically how do children comprehend utterances in terms of who is doing what to whom?

History

The model was first built at the NCSA GPU Hackathon in 2018. It was updated to work with tensorflow 2.0 while working under the supervision of Cynthia Fisher in the Department of Psychology at UIUC.

Differences with original implementation

• LSTMs are initialized with orthogonal matrices (instead of orthonormal matrices used by He et al., 2017)
• Decoding constraints are not implemented (BIO tag sequence constraints, SRL sequence constraints)
• Control gates governing highway connections between LSTM layers are not implemented
• Recurrent dropout is not used because it prevents using cudnn acceleration of the LSTM computations in tensorflow 2.0

Allen NLP implementation

The original model was ported to pytorch by Allen NLP and is made available via the Allen NLP toolkit. The Allen NLP implementation is included in this repository to accurately compare performance between it and the tensorflow-based implementation.

To train the Allen NLP implementation, set params.param2requests['model'] = 1 The F1 score on the development set for the first three epochs should be approximately:

• epoch 0: ~ 0
• epoch 1: ~22
• epoch 2: ~43
• epoch 3: ~50

Compatibility

Tested on Ubuntu 16.04, Python 3.6 and tensorflow-gpu 2.0.0rc1