An Improved Left-Corner Parsing Algorithm
نویسنده
چکیده
G r i f f i t h s and Pet.rick (1965) propose several algori thms for recognizing sentences of contex t f ree grammars in the general case One of these algor i thms, the NBT (Non-select ive Bottom to Top) Algor i thm, has since been ca l led a " l e f t c o r n e r " algor i thm. Of l a te , i n te res t has been rekindled in l e f t co rne r parsers. Chester (1980) proposes a modi f ica t ion to the G r i f f i t h s and Petr ick a lgor i thm which "combines phrases before i t has found a l l of t h e i r components." Slocum (1981) shows that a l e f t co rne r parser inspi red by G r i f f i t h s and Pet r i ck 's a lgor i thm and by Chester's performs qui te well when compared with parsers based on a Cocke-KasamiYounger a lgor i thm (see Younger 1967).
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