The 31st UW/MS Symposium in Computational Linguistics


November 1, 2013


Emily M. Bender, Woodley Packard, and Margaret Mitchell


University of Washington, Microsoft Research


Woodley Packard and Emily M. Bender: Predicting the Scope of Negation using Minimal Recursion Semantics:

Negation is a pervasive phenomenon in natural language, occurring in every language and every genre. Despite the obviously profound impact of negation on the meaning of a sentence, the most common approach to handling negation in NLP systems is to ignore it, leading to all manner of (frequently) comical errors. To encourage the exploration of better solutions, the 2012 *SEM Shared Task focused (among other things) on automatically identifying negation and determining its scope. Several of the resulting systems were quite successful, but despite the semantic nature of the task, the vast majority of them were based on surface or syntactic methods. In this talk, we will describe a semantics-based method of attacking the same problem. Our system is based on the Minimal Recursion Semantics structures produced by the English Resource Grammar, a broad-coverage, precision, computational HPSG account of English. We show that it is relatively straightforward to design high precision rules to determine what portion of a sentence is within the scope of negation, by “crawling” through these graphs. In a system combination with the winner of the 2012 competition, our method yields improved precision and F1. Moreover, our “crawling” rules can be seen as a first-pass formalization of the shared task annotation guidelines.

Margaret Mitchell: Generating human reference to visible objects:

In this talk, I will detail some previous work on how people refer to everyday objects in real world settings, and discuss how to model this in a generation system that produces humanlike descriptions. This talk will tie in aspects of linguistics, cognitive science, and statistical natural language processing.


Emily M. Bender, Woodley Packard, and Margaret Mitchell

Emily M. Bender is an Associate Professor of Linguistics and Adjunct Associate Professor of Computer Science and Engineering at the University of Washington. She is the Faculty Director of UW’s Professional Masters Program in Computational Linguistics (CLMS). Her research interests center on multilingual grammar engineering, computational semantics, and the relationship between linguistics and computational linguistics. Her book,Linguistic Fundamentals for Natural Language Processing: 100 Essentials from Morphology and Syntax_ appeared this year in Morgan & Claypool’s Synthesis Lectures in Human Language Technologies.

Woodley Packard is currently a CLMS student at the University of Washington. Since completing his M.S. and B.S. in Mathematics at Stanford University in 2006, he spent three years at a web technology startup, and has also spent time at the University of Oslo in Norway. He is also the author of the ACE parser-generator and various other experimental NLP tools.

Margaret Mitchell received her Master’s from the University of Washington’s CLMA program and her PhD at the University of Aberdeen. She also spent several years at Oregon Health and Science University as a visiting scholar. Her research has recently focused on connecting vision to language.


  • Portrait of Margaret Mitchell

    Margaret Mitchell