Arithmetic Sampling

This codebase allows for use of the Arithmetic Sampling algorithm for sampling from sequence models in T5X.

Introduction

Arithmetic Sampling is an algorithm for sampling from sequence models that provides provably increased beam diversity compared to regular sampling in some situations, as well as lowered estimator variance. The algorithm is also parallelizable.

How to use arithmetic sampling

This library provides a T5X implementation of the algorithm for use with any model that can accept an EncoderDecoderModel.decode_fn, though implementations for other model types should be quite straightforward. The gin files in this library can be included in any compatible T5X model to use arithmetic sampling.

The easiest way to get started on accelerators is to plug one of the included gin configs into the T5X Quickstart guide.

Parallel decoding can be accomplished by pre-computing the codes for each sample, fixing the RNG seed, and passing them in batches along with the codes.

The included run.sh will install locally (including installing t5x from GitHub) and run the tests with a fallback to CPU mode.