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Chad Dionis

 Fido Database Design 

Ellipsis Concepts

In the Object Hierarchy, objects relate to each other with a parent - child relationship. When comparing nouns for ellipsis matching, the Noun Hierarchy is the path from the object, through each parent, to the root of the tree.

To illustrate comparing two objects using the Noun Hierarchies, refer to the following example sentence pairs:

  • Put the milk in the fridge
  • the juice
The fragment noun in the second sentence the juice could replace either the milk or the fridge. As humans, we know the speaker meant to put the juice in the fridge, not the milk in the juice. The Fido system will determine this by matching the fragement noun to the closed subtree in the previous sentence.

This is a sample noun hierarchy:

Using this hierarchy, the nouns milk and fridge in the first sentence would have the Noun Hierarchy of
Object
|
Object
|
Inanimate
Object
|
Inanimate
Object
|
Food
|
Container
|
Dairy
|
Fridge
Milk
The noun juice in the second sentence would have the following:
Object
|
Inanimate
Object
|
Food
|
Citris
|
Juice
To determine which noun in the first sentence to replace, start with the bottom of the hierarchy for the second fragement noun. In this example, we will take juice and look for it in the hierarchies of all nouns in the previous sentences. It did not exist. Then take the next entry in the hierarchy citris. This did not exist either. Then take food. This entry shows up in the hierarchy for milk. This is a match, but we must ensure that the entry found, food does not exist in the other previous noun. Basically this would not allow a word to replace one food, when both nouns in the previous were foods.

We take the entry food and look it up in the other nouns in the previous sentence. In this case, just fridge. It did not exist, and we have one, and only one, match.

Examples

  1. Noun (command) - The direct object.
    1. Put the milk in the fridge.
    2. The cereal in the pantry.
  2. Verb - The verb phrase did too will resolve to the previous verb phrase, lost his wallet.
    1. Jack lost his wallet.
    2. Sam did too.
  3. Noun - Because the bananas is in the same subtree as the peaches, through semantics, the direct object was replaced. Also, sentence structure.
    1. Did Sam find the bananas?
    2. Yes.
    3. The peaches?
  4. Noun - Through sentence structures, the ice cream replaces the bananas.
    1. Did the clerk put the bananas on the shelf?
    2. Yes.
    3. The ice cream in the refrigerator?
  5. Noun - In the following, the TV dinners has the same sentence structure as the clerk and the ice cream. Therefore the only was to identify the antecedent is through semantics. Ice cream is in the same subtree in the Object Hierarchy as TV dinners (both food).
    1. Did the clerk put the ice cream in the refrigerator?
    2. No.
    3. The TV dinners.
  6. Noun - Again, the sentence structure could have the toaster oven replace either the clerk or the store. Simple Object Hierarchy tree analysis will not identify with phrase in the previous sentence will be replaced. This needs deep knowledge understanding of space. Since the clerk would be too large to be inside of a toaster oven, the clerk phrase would not be replaced. See also Verb Constraints.
    1. Did you see the clerk in the store?
    2. Yes
    3. The toaster oven?
  7. Noun - Even through the preposition is different, the structure identifies which phrase to replace.
    1. Get the bananas on the counter.
    2. Yes.
    3. The oranges in the pantry.
  8. Combination
    1. How many went to Richmond last month?
    2. How many to Durham?
    3. To Fairfax this month?
===========================
Put the milk in the fridge.
===========================

       +--- DO ---+        +--- PO ---+
       |          |        |          |
 +- V -+    +- A -+- PREP -+    +- A -+
 |     |    |     |        |    |     |

///   Put  the  milk       in  the  fridge


///  <- V    -> Put
Put  <- DO   -> milk
the  <- A    -> milk
milk <- PREP -> in 
in   <- PO   -> fridge
the  <- A    -> fridge

=========================
The cereal in the pantry.
=========================

 +--- NP ---+        +--- PO ---+
 |          |        |          |
 |    +- A -+- PREP -+    +- A -+
 |    |     |        |    |     |

///  The  cereal     in  the  pantry


///    <- NP   -> cereal
the    <- A    -> cereal
cereal <- PREP -> in 
in     <- PO   -> pantry
the    <- A    -> pantry

==============
In the pantry.
==============

          +--- PO ---+
          |          |
 +- PREP -+    +- A -+
 |        |    |     |

///       in  the  pantry


///    <- PREP -> in
in     <- PO   -> pantry
the    <- A    -> pantry

==========
The juice.
==========

 +--- NP ---+
 |          |
 +    +- A -+
 |    |     |

/// The juice


/// <- NP -> the
the <- A  -> juice

* This example requires semantic analysis:
1.  Put the juice in the fridge.
2. ?Put the milk in the juice.

==========
The glass.
==========

 +--- NP ---+
 |          |
 +    +- A -+
 |    |     |

///  The  glass


/// <- NP -> the
the <- A  -> juice

* This example requires semantic analysis:
1.  Put the milk in the glass.
2. ?Put the glass in the fridge.

* Most likely will need to ask user the intent.
Last modified: February 03 2003 16:01:54
© 2002 Fido Development Team