LCS and Approximate Interlingua at UMD Semantic Annotation Planning Meeting April 14, 2004 Bonnie J. Dorr University of Maryland

Lexical Conceptual Structure (LCS) LCS is composed of semantic primitives and semantic domains (Jackendoff, Dorr) Primitives: CAUSE, GO, BE, STAY, etc. Domains: Location, Identity, Communication Associated Features Theta roles (relations between entities and events) Mapping to Propbank roles Levin class WordNet sense(s) Argument features Lexical-semantic argument structure What is missing? Speech acts Relations between entities Beliefs, certainty, truth, falsehood Mappings that enable paraphrase recognition/generation This is the new piece to be added in Approx Interlingua

English LCS Lexicon Entry ( :DEF_WORD "enter"enter :CLASS "51.1.a"51.1.a :WN_SENSE (("1.5" )("1.6" ) ("1.7.1" ) ("2.0" )) :PROPBANK ("arg1 arg2(from) arg2(to)") :THETA_ROLES ((1 "_th,src(from),goal(to)")) :LCS (go loc (* thing 2) ((* from 3) loc (thing 2) (at loc (thing 2) (thing 4))) ((* [to] 5) loc (thing 2) ([at] loc (thing 2) (thing 6)) (enter+ingly 26)) :VAR_SPEC ((5 :optional) (3 :optional) (2 (animate +))) ) AGENT THEME SOURCE GOAL PREDICATE PERCEIVED LOCATION POSSESSED TIME BENEFICIARY INSTRUMENT PURPOSE PROPOSITION

What we annotate (to be talked about in context of IAMTC)

Approximate Interlingua (AIL) Same features as LCS, except: Argument structure is shallower: Top-level semantic primitives, e.g., CAUSE, GO, BE, STAY, are retained. Enables paraphrase via CatVar features: Allow expansion of any TL words to their other parts of speech excel V at directing N directs V well ADV excellent ADV directorship N Tralex: dirigir  {direct, guide, drive } buen  { well, good, excellent } The organization excels at directing ground operations. vs. The organization directs ground operations well. vs. The organization provides excellent directorship of ground operations. CatVar is downloadable:

Comparison of LCS to AIL The struggle against the drug lords in Colombia will be a near thing