Laurent El Shafey


2022

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Knowledge-grounded Dialog State Tracking
Dian Yu | Mingqiu Wang | Yuan Cao | Laurent El Shafey | Izhak Shafran | Hagen Soltau
Findings of the Association for Computational Linguistics: EMNLP 2022

Knowledge (including structured knowledge such as schema and ontology and unstructured knowledge such as web corpus) is a critical part of dialog understanding, especially for unseen tasks and domains. Traditionally, such domain-specific knowledge is encoded implicitly into model parameters for the execution of downstream tasks, which makes training inefficient. In addition , such models are not easily transferable to new tasks with different schemas. In this work, we propose to perform dialog state tracking grounded on knowledge encoded externally. We query relevant knowledge of various forms based on the dialog context where such information can grounds the prediction of dialog states. We demonstrate superior performance of our proposed method over strong baselines, especially in the few-shot learning setting.

2020

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The Medical Scribe: Corpus Development and Model Performance Analyses
Izhak Shafran | Nan Du | Linh Tran | Amanda Perry | Lauren Keyes | Mark Knichel | Ashley Domin | Lei Huang | Yu-hui Chen | Gang Li | Mingqiu Wang | Laurent El Shafey | Hagen Soltau | Justin Stuart Paul
Proceedings of the Twelfth Language Resources and Evaluation Conference

There is a growing interest in creating tools to assist in clinical note generation using the audio of provider-patient encounters. Motivated by this goal and with the help of providers and medical scribes, we developed an annotation scheme to extract relevant clinical concepts. We used this annotation scheme to label a corpus of about 6k clinical encounters. This was used to train a state-of-the-art tagging model. We report ontologies, labeling results, model performances, and detailed analyses of the results. Our results show that the entities related to medications can be extracted with a relatively high accuracy of 0.90 F-score, followed by symptoms at 0.72 F-score, and conditions at 0.57 F-score. In our task, we not only identify where the symptoms are mentioned but also map them to canonical forms as they appear in the clinical notes. Of the different types of errors, in about 19-38% of the cases, we find that the model output was correct, and about 17-32% of the errors do not impact the clinical note. Taken together, the models developed in this work are more useful than the F-scores reflect, making it a promising approach for practical applications.