Friday, February 28, 2014

Natural Language Processing

Natural Language
Refers to the language spoken by people, e.g. English, Japanese, as opposed to artificial languages, like C++, Java, etc.


Natural Language Processing
NLP is the branch of computer science focused on developing systems that allow computers to communicate with people using everyday language.NLP is related to human -computer interaction.  NLP encompasses anything a computer needs to understand natural language and also generate natural language.NLP is a sub field of artificial intelligence. Devoted to make computers “understand” statements  written in human language. 

Why Natural Language Processing  
kJfmmfj  mmmvvv  nnnffn333

Uj iheale eleee mnster vensi credur

Baboi oi cestnitze

Coovoel2^ ekk; ldsllk lkdf vnnjfj?

Fgmflmllk mlfm kfre xnnn!
Computers “see” text in English the same we have seen the above text!
People have no trouble understanding language 
  • Common sense knowledge 
  • Reasoning capacity 
  • Experience 
Computers have 
  • No common sense knowledge 
  • No reasoning capacity 
 that’s why we need natural language processing. 

Steps in natural language processing
 
Morphological analysis
Individual words are analyzed into their component and non word tokens. punctuation are separated from word .
e.g   carried= carry+ed

Syntactic analysis
.grammatical structure of sentence is analyze. some word sequence may be rejected if they violate the rules of language . e.g  syntactic analyzer reject the sentence 
  Boy the go  the to store


Semantic analysis
. determine possible meaning of sentence.
. Sentence which has no meaning is rejected.
. For eg “ colorless green ideas ” has no meaning.

Discourse Analysis
. The meaning of  an individual sentence may depends on  the sentence that precede it and may influence the meaning of sentences that follow it.
e.g  “john wanted it” the word ‘it’  depends upon john.


Pragmatic analysis
. It derives knowledge from external commonsense information.
. It means understanding purposeful use of language in situation.
e.g   “ DO you know what time it is?”
   should be interpreted as a request.