NL Semantics Meaning Representations

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NL SemanticsMeaning Representations
Read J M Chapter 14.
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Why Meaning?

• Meaning is a function of the application
• Front end to an application system
• Find me a cheap Italian restaurant.
• Whats the weather in Austin.
• Drive to Houston.
• Text retrieval Suppose we want fad gifts to
  match
  
• pet rock
• cabbage patch dolls
• latest trends for Christmas
• MT

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Representing the Meaning of Sentences
John saw Bill. John has a cat. John saw Bill
(another try) John has a cold. John served Bill
. John served the team. John served steak. Kirb
y Lane serves vegetarian food.
Mothers is a vegetarian restaurant.
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More Examples - Price
Mothers costs less than 10. Mothers is cheap.
Mothers is on Duval. Mothers is on the
Chronicles list.

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More Examples Eating Restaurants

• I want to eat Italian food.
• I want to eat someplace that serves Italian food.

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More Examples Mary and Sue

• Mary is Sues sister.
• Sue is Marys sister.

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More Examples Possessives
Mary is Sues sister. Mary read Sues book. Mary
washed her hands. Marylands capital is Annapoli
s.
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More Examples - Adjectives
cheap restaurant modest mansion former friend f
ake gun
We can try to figure out the correct semantic
relationship or we can introduce a vague relation
and work it out later.
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More Examples Vague and Relative Words

• Agnes is a big cat.
• Agnes is a big tiger.
• Agnes is big.
• Mary is stunning.
• Susan is old-fashioned.

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More Examples Relating Objects
leather jacket riding jacket winter jacket

letter jacket
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More Examples Events

• I ate lunch.
• I ate a turkey sandwich.
• I ate in my office.
• I eat lunch every day.
• I eat lunch at noon.

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More Examples Quantifiers and Logic
Everyone ate a cookie. The team built a house.
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Sentences that Arent Declarative
1. Does John have a cat? 2. Close the window. 3.
Can you close the window? 4. Do you sell pretzel
s?
5. I need to know whether you sell pretzels.
Language as action. The theory of speech acts.
But what about other applications like MT?
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Representing Belief

• Borders is open until midnight.
• Mary believes that Borders is open until
  midnight.
  
• Borders is the biggest bookstore in town.
• Conclude, from 1 and 3, that The biggest
  bookstore in town is open until midnight.
  
• Can we conclude that Mary believes that the
  biggest bookstore in town is open until midnight.