Led the research of end-to-end natural language understanding (NLU) deep neural network (DNN) models for Alexa, simplifying the NLU system by directly predicting user intent and keywords from audio signal. On offline test sets, it reduced error rate by 2% for all input, and by 8% for noisy input, compared to two-stage production baseline.
Launched context-aware NLU DNN models to help Alexa understand multi-turn dialog better. Built representation learning models for encoding user dialog history, and data pipelines for fetching contextual data. It reduced user dissatisfaction rate by up to 10% in online A/B tests, and was deployed into more than 5 Alexa production models.
Developed prototype DNN models in MXNet and PyTorch, run-time model serving and data pipelines in C++, and offline data pipelines for training/testing in Python and Spark.