Introduction to Cognitive Psychology - Department of Psychological ...

Greg Francis 1/6/11Phrase tree!! It helps to describe rules as phrase trees!! Specifies both what can be used in thephrase and where it must be usedNPdet A NPhrases!! Similarly, there are rules for all sorts ofphrases in a language!! There may be many ways to rewrite aphrase!S-->NP VPVP-->V NPS -- sentenceNP -- noun phraseVP -- verb phrasethe happy boyPurdue UniversityPurdue UniversityLexicon!! We also need a mental dictionary(lexicon) that specifies parts of speech!!N --> boy, girl, candy, hot dogs, ice cream,…!!V --> eats, likes, bites,…!!det --> a, the, one,…!!A --> lucky, tall,...Purdue UniversityPhrase tree!! With rewrite rules and a mental dictionary,you can create a sentence by linking therules togetherSNPVPVNPdet A NNthe happy boyeatsice creamPurdue UniversitySockets!! In a phrase tree, a phrase is like a componentthat snaps into the right placedetthe!!any appropriate phrase works! (even nonsensephrases)SNPVPVNPA A NNcolorless green idea eatsice creamPurdue UniversityUsefulness!! It is important to appreciate how the phrase treeapproach simplifies the description of language!! Consider how we learn a new word and knowhow to use it!! If you learn that a word is a noun, you canimmediately use that noun in many differentwaysPurdue UniversityPSY200 Cognitive Psychology 4