NLU Syntax Flashcards
(25 cards)
What is Natural Language Understanding (NLU)?
NLU is a field of AI that focuses on machine understanding of human language using syntax, semantics, and pragmatics.
What is the motivation behind NLU?
To bridge the gap between human and machine communication.
What is a language?
A collection of sentences of finite length all constructed from a finite alphabet of symbols.
What is a grammar?
A device that enumerates the sentences of a language.
What is speech recognition in NLU?
The process of identifying spoken words and converting them into text.
What is syntactic analysis?
Analyzing the grammatical structure of a sentence.
What is semantic analysis?
Understanding the meaning of a sentence using knowledge about objects and actions.
What is pragmatic analysis?
Understanding language in context, such as interpreting ‘You have a green light’ based on situation.
What is a formal grammar?
A tuple G = (N, Σ, P, S) where N is non-terminals, Σ is terminals, P is production rules, and S is the start symbol.
What are the levels of the Chomsky Hierarchy?
Type-0: Unrestricted, Type-1: Context Sensitive, Type-2: Context Free, Type-3: Regular.
Which automaton accepts Type-0 grammars?
Turing machines.
Which automaton accepts Type-1 grammars?
Linear-bounded automata.
Which automaton accepts Type-2 grammars?
Push-down automata.
Which automaton accepts Type-3 grammars?
Finite state automata.
What is a Context-Free Grammar (CFG)?
A grammar where rules are of the form A → α, where A is a non-terminal and α is a string of terminals and/or non-terminals.
What is a Definite Clause Grammar (DCG)?
A Prolog-based notation for CFGs using –> to define grammar rules.
How are terminal symbols denoted in DCG?
Terminal symbols appear inside square brackets, e.g. [man].
How is the rule ‘noun → man’ represented in DCG?
noun –> [man].
What does a lexical analyzer do?
Transforms input phrases into a list of tokens.
What are two main functions of a parser?
Syntax checking and syntax tree generation.
What is a parse tree?
A tree representation of the syntactic structure of a sentence.
What is the Prolog representation of ‘sentence –> noun_phrase, verb_phrase.’?
sentence(ListOfTerminals, Result) :- noun_phrase(ListOfTerminals, TmpList), verb_phrase(TmpList, Result).
What are applications of NLU and grammars?
Grammar checkers, translation systems, TTS, STT, summarization, free-text interfaces, compiler design.
What is a limitation of LLMs like GPT in NLU?
They predict text sequences statistically but do not truly understand language.
