1 Pertemuan 24 Natural Language Processing Discourse and Pragmatic Processing Matakuliah: T0264/Intelijensia Semu Tahun: Juli 2006 Versi: 2/4

2 Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : >

3 Outline Materi Materi 1 Materi 2 Materi 3 Materi 4 Materi 5

Discourse and Pragmatic Processing To Understand even a single sentence Important when we want to understand texts and dialogues. There are a number of important relationships that may holt between phrases and part of their discourse context, including :

5 Discourse and Pragmatic Processing Identical entities (anaphora). Bill had a red balloon. John wanted it Parts of entities. Sue opened the book she just bought. The title page was torn. Parts of actions. John went on a business trip to New York. He left on an early morning flight.

6 Discourse and Pragmatic Processing contd’ Entities involved in actions. My house was broken into last week. They took the TV and the stereo. Elements of sets. The decals we have in stock are stars, the moon, item and a flag. I’ll take two moons. Names of individuals. Dave went to the movies.

7 Discourse and Pragmatic Processing contd’ Causal chains. There was a big snow storm yesterday. The schools were closed today. Planning sequences. Sally wanted a new car. She decided to get a job. Illocutionary force. It sure is cold in here. Implicit presuppositions. Did Joe fail CS101 ?

Using Focus in Understanding There are two important part of the process of using knowledge to facilitate understanding : 1. Focus on the relevant part(s) of the available knowledge base. 2. Use that knowledge to resolve ambiguities and to make connections among thing that were said.

9 Using Focus in Understanding Example To make the torte, first make the cake, then, while the cake is baking, make the filling. To make the cake, combine all ingredients. Pour them into the pans, and bake for 30 minutes. To make the filling, combine the ingredients. Mix until light and fluffy. When the cake is done, alternate layers of cake and filling. This task decomposes into three subtasks : making the cake, making the filling, and combining the two components. The structure of the paragraph of instructions is : overall sketch of the task, instructions for step 1, instructions for step 2, and then instructions for step 3.

Modeling Beliefs Modeling Shared beliefs - Select the appropriate script(s) from memory. - Use the script(s) to fill in unspecified parts of the text to be understood. Modeling Individual beliefs BELIEVE(A,P)  P  KNOW(A,P) Three different that Mary hit Bill : - S1 believes that Mary hi Bill. - S2 believes that Sue hit Bill. - S3 believes that someone hit Bill

11 Modeling Beliefs contd’ A Partitioned Semantic Net with Three Belief Spaces

Goals and Plans Consider the text John was anxious to get his daughter’s new bike put together before Christmas Eve. He looked high and low for a screwdriver. To understand this story, we need to recognize that John had: –A goal, getting the bike put together. –A plan, which involves putting together the various subparts until the bike is complete. At least one of the resulting sub-plans involves using a screwdriver to screw two parts together.

13 Common Goals Satisfaction goals, such as sleep, food, and water. Enjoyment goals, such as entertainment and competition. Achievement goals, such as possession, power, and status. Preservation goals, such as health and possessions. Pleasing goals, which involve satisfying some other kind of goal for someone else. Instrumental goals, which enable preconditions for other, higher-level goals

14 Plan Operators USE(A,P,G): precondition :KNOW-WHAT(A,LOCATION(P)) NEAR(A,P) HAS-CONTROL-OF(A,P) READY(P) postcondition :DONE(G) LOOK-FOR(A,P) : precondition : CAN-RECOGNIZE(A,P) postcondition: KNOW-WHAT(A,LOCATION(P))

Speech Acts INFORM(A,B,P) : precondition : BELIEVE(A,P) KNOW-WHAT(A,LOCATION(B)) postcondition : BELIEVE(B,BELIEVE(A,P)) BELIEVE-IN(B,A) ( BELIEVE(B,P) ASK-WHAT(A,B,P) : precondition : KNOW-WHAT(A,LOCATION(B)) KNOW-WHAT(B,P) WILLING-TO-PERFORM (B,INFORM(B,A,P)) postcondition :KNOW-WHAT(A,P)

16 Speech Acts contd’ REQUEST(A,B,R) : precondition : KNOW-WHAT(A,LOCATION(B)) CAN-PERFORM(B,R) WILLING-TO-PERFORM(B,R) postcondition : WILL(PERFORM(B,R))

Conversational Postulates Sincerity Conditions A : Can you open the door ? Reasonableness Conditions A : Can you open the door ? B : Why do you want it open ? Appropriateness Conditions A : Who won the race ? B : Someone with long, dark hair. A : I thought you knew all the runners.

18 > End of Pertemuan 24 Good Luck