语义网FNintroCJF.ppt

FrameNet The work. The product. The applications. CJFillmore - ICSI/Berkeley Acknowledgements International Computer Science Institute National Science Foundation Defense Advanced Research Projects Agency Frames and Understanding Hypothesis: People understand things by performing mental operations on what they already know. Such knowledge is describable in terms of information packets called frames. The core work of FrameNet characterize frames find words that fit the frames develop descriptive terminology extract sample sentences annotate selected examples derive valence descriptions D I G R E S S I O N Actually there are two contexts in which you will probably be asked to do FrameNet annotations. One is for purely lexicographic purposes, where you will choose “good examples” of the use of each word. The other is for full text analysis, where you will analyze every word in a text. The description that follows concentrates on the lexicographic work The core work of FrameNet characterize frames find words that fit the frames develop descriptive terminology extract sample sentences annotate selected examples derive valence descriptions Finding words that belong in a given frame We look for words in the language that bring to mind the individual frames. We say that the words evoke the frames. “Words”? But first there’s an enemy we have to deal with: polysemy, lexical ambiguity, multiple meanings of a single “word”. Instead of words, we have to work with lexical units (LUs), each of these being a pairing of a word with a sense. FrameNet is at the “splitting” end of the “splitting” versus “lumping” continuum when it comes to the monosemy/polysemy. What could count as evidence for the separateness of lexical units with the same form? Discernible meaning differences. If a word communicates different meanings in different contexts, and the difference isn’t explained by the contexts, maybe the word has more than one meaning. She earns a lot less t