Adaptive command predictor and method for a natural language dialog system

• US 6,622,119 B1
• Filed: 10/30/1999
• Issued: 09/16/2003
• Est. Priority Date: 10/30/1999
• Status: Expired due to Term

• Current Assignee: Nuance Communications, Inc. (Microsoft Corporation)
• Original Assignee: International Business Machines Corporation
• Inventors: Ramaswamy, Ganesh N., Kleindienst, Jan
• Primary Examiner(s): EDOUARD, PATRICK NESTOR
• Application Number:
  US09/431,034
• Time in Patent Office: 1,417 Days
• Field of Search: 704/1, 704/9, 704/10, 704/257, 704/270, 704/275, 707/531, 707/532, 707/533, 706/47, 706/49, 706/53, 706/54.55
• US Class Current: 704/9
• CPC Class Codes: G06F 40/274 Converting codes to words; Guess-ahead of partial word inputs
• CPC Class Codes: G06F 40/35 Discourse or dialogue representation

Abstract

A command prediction system for natural language understanding systems, in accordance with the present invention, includes a user interface for receiving commands from a user. A command predictor receives the commands from the user interface and predicts at least one next command which is likely to be presented by the user based on a command history. A probability calculator is included in the command predictor for determining a probability for each of the at least one next command based on the command history such that a list of predicted commands and their likelihood of being a next command are provided.

Claims

1. A command prediction system for natural language understanding systems comprising:

a user interface for receiving commands from a user;

a command predictor for receiving the commands from the user interface and predicting at least one next command which is likely to be presented by the user based on a command history;

a probability calculator being included in the command predictor for determining a probability for each of the at least one next command based on the command history such that a list of predicted commands and their likelihood of being a next command are provided; and

a natural language engine for processing the list of predicted commands and associated probabilities to convert a command from the user to formal language command.

2. The system as recited in claim 1, wherein the natural language engine employs the list of predicted commands to weight the commands to provide a most likely next command for execution.

3. The system as recited in claim 1, further comprising a dialog manager coupled to the command predictor for prompting a user for a response based on a most probable next command from the list of predicted commands.

4. The system as recited in claim 1, wherein the user interface receives an access method of the user, and the command predictor further comprises a prediction model, the prediction model for storing frequencies of issued command sequences and the access method for predicting the at least one next command.

5. The system as recited in claim 4, wherein the prediction model includes a personal prediction model which is constructed for a given user based on previously issued commands and access methods.

6. The system as recited in claim 1, wherein the command history stores at least two commands previously issued in one of a same session and a predetermined time interval.

7. A command prediction system comprising:

a natural language understanding engine coupled to a user interface for receiving commands from a user and converting the commands to formal language commands;

a command predictor for receiving the formal language commands from the natural language engine and for predicting at least one next command which is likely to be presented by the user;

a dialog manager coupled to the command predictor and the user interface for prompting user action responsive to the predicted at least one next command.

8. The system as recited in claim 7, wherein the command predictor includes a command history for storing commands employed by the user.

9. The system as recited in claim 8, wherein the command predictor includes a prediction model which stores frequencies of command sequences and access methods associated with the command sequences used to predict the at least one next command.

10. The system as recited in claim 9, wherein the command predictor includes a probability calculator coupled to the command history and the prediction model, the probability calculator for determining a list of predicted commands and associated probabilities of a likelihood of being the next command based on input from the command history and the prediction model.

11. The system as recited in claim 8, wherein the prediction model includes a personal prediction model for a given user, the personal prediction model being constructed from a personal training corpus and based on a command history of the given user.

12. A method for predicting a next command in a natural language understanding system comprising the steps of:

receiving commands from a user by employing a user interface;

receiving the commands from the user interface at a command predictor;

the command predictor predicting at least one next command which is likely to be presented by the user based on a command history;

determining a probability for each of the at least one next command based on the command history such that a list of predicted commands and their likelihood of being a next command are provided; and

processing the list of predicted commands and associated probabilities to convert a command from the user to formal language command using a natural language understanding engine.

13. The method as recited in claim 12, wherein the step of converting includes the step of weighting the list of predicted commands to provide a most likely next command for execution.

14. The method as recited in claim 12, further comprising the step of prompting a user for a response based on a most probable next command from the list of predicted commands by employing a dialog manager coupled.

15. The method as recited in claim 12, wherein the command predictor includes a prediction model and further comprising the step of receiving an access method of the user such that the prediction model employs frequencies of issued command sequences and the access method for predicting the at least one next command.

16. The method as recited in claim 15, wherein the prediction model includes a personal prediction model and further comprising the step of constructing the personal prediction model for a given user based on previously issued commands and access methods.

17. A program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform method steps for predicting a next command in a natural language understanding system, the method steps comprising:

receiving commands from a user by employing a user interface;

receiving the commands from the user interface at a command predictor;

the command predictor predicting at least one next command which is likely to be presented by the user based on a command history;

determining a probability for each of the at least one next command based on the command history such that a list of predicted commands and their likelihood of being a next command are provided; and

processing the list of predicted commands and associated probabilities to convert a command from the user to formal language command using a natural language understanding engine.

18. The program storage device as recited in claim 17, wherein the step of converting includes the step of weighting the list of predicted commands to provide a most likely next command for execution.

19. The program storage device as recited in claim 17, further comprising the step of prompting a user for a response based on a most probable next command from the list of predicted commands by employing a dialog manager coupled.

20. The program storage device as recited in claim 19, wherein the command predictor includes a prediction model and further comprising the step of receiving an access method of the user such that the prediction model employs frequencies of issued command sequences and the access method for predicting the at least one next command.

21. The program storage device as recited in claim 20, wherein the prediction model includes a personal prediction model and further comprising the step of constructing the personal prediction model for a given user based on previously issued commands and access methods.