Morphology technology
• Different applications -- different needs
– stemmers
• collapse all forms of a word by pairing with “stem”
– for (CL)IR
– for (aspects of) language modeling
– analysis/synthesis
• pair wordform with lemma+affixes/features (or more)
• perhaps with disambiguation in textual context
– for spelling correction
– for pronunciation calculation
– for language modeling
– for information extraction
– for translation
• All cases can be modeled as  relations on strings
2/5/01