Cognitive arbitration system

• US 7,340,443 B2
• Filed: 05/14/2004
• Issued: 03/04/2008
• Est. Priority Date: 05/14/2004
• Status: Expired due to Fees

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Tillotson, Dennis A., Lewis, Lori K., Paradis, Rosemary D., Dugan, Peter
• Primary Examiner(s): Knight; Anthony
• Assistant Examiner(s): Brown, Jr.; Nathan H.
• Application Number:
  US10/846,407
• Publication Number:
  US 20050256820A1
• Time in Patent Office: 1,390 Days
• Field of Search: 706/52
• US Class Current: 706/52
• CPC Class Codes: G06F 18/254 of classification results, e.g. of results related to same input data
• CPC Class Codes: G06N 7/02 using fuzzy logic computing arrangements based on biological models G06N3/00; computing arrangements using knowledge-based models G06N5/00

Abstract

A method and computer product is disclosed for arbitrating the outputs of a plurality of recognizers to select a hypothesis associated with a given input from a plurality of hypotheses. Fuzzy membership states are assigned to respective candidate outputs of the plurality of recognizers. At least one rule is selected according to the assigned fuzzy membership states. A selected rule provides a determined amount of support mass for an associated one of the plurality of hypotheses and a determined amount of uncertainty mass. A support value for each hypothesis and an overall uncertainty are determined from the provided mass values. A hypothesis having a highest support value while having an acceptable low level of uncertainty is selected.

Claims

1. A machine, having a memory comprising data representing a plurality of hypotheses and associated support values for the plurality of hypotheses, the data being a product of a process comprising the steps of:

generating candidate outputs, representing an input pattern, at a plurality of recognizers;

assigning fuzzy membership states to respective candidate outputs of the plurality of recognizers;

selecting at least one rule according to the assigned fuzzy membership states, a selected rule providing a determined amount of support mass for an associated one of the plurality of hypotheses and a determined amount of uncertainty mass;

determining a support value for each hypothesis and an overall uncertainty value from the provided mass values;

comparing the support value for the selected hypothesis to a first threshold value;

comparing the overall uncertainty value to a second threshold value;

accepting the selected hypothesis if the support value meets the first threshold and the overall uncertainty value is below the second threshold value; and

outputting a negative result if the selected hypothesis is not accepted.

2. A machine as set forth in claim 1 wherein the step of determining a total support value for a given hypothesis includes multiplying the associated support masses for a plurality of selected rules associated with the hypothesis to form a support value and multiplying the associated uncertainty mass for the plurality of selected rules associated with the hypothesis to form an uncertainty value.

3. A machine as set forth in claim 2 wherein computing the overall uncertainty value includes summing the uncertainty value associated with each hypothesis across the plurality of hypotheses.

4. A machine as set forth in claim 2 wherein each rule has an associated priority value and the associated mass for the rule is weighted by the priority value.

5. A machine as set forth in claim 4, wherein the associated priority values of the plurality of rules are configurable by a user to adjust the relative importance of each rule.

6. A machine as set forth in claim 1 wherein the each of the plurality of recognizers produces a plurality of candidate outputs, each associated with one of the plurality of hypotheses and ranked by associated output scores, and the at least one rule is selected according to the assigned fuzzy membership states and the ranking of the candidate outputs.

7. A machine as set forth in claim 1 wherein at least one of the plurality of recognizers includes a pattern recognition classifier, and a given hypothesis is associated with an output class of the at least one pattern recognition classifier.

8. A machine as set forth in claim 1, the process further comprising the step of normalizing the support values and the overall uncertainty to a desired scale.

9. A machine as set forth in claim 8, the process further comprising the step of computing a plausibility range for each hypothesis from the normalized values.

10. A computer-readable medium operative in a data processing system, that stores executable instructions for arbitrating the outputs of a plurality of recognizers to select a hypothesis for a given input from a plurality of hypotheses, the executable instructions comprising:

a fuzzy class assignment routine that assigns a fuzzy membership state to respective at least one candidate outputs of the plurality of recognizers;

a rule selection routine that evaluates a plurality of rules according to the assigned fuzzy membership states of the candidate outputs to determine which of the plurality of rules apply to each of the plurality of output hypotheses, an applicable rule providing a determined amount of support mass for an associated hypothesis and a determined amount of uncertainty mass; and

a data fusion routine that determines a support value for each hypothesis and an overall uncertainty value from the provided mass values, normalizes the support values for the plurality of hypotheses to determine associated belief and plausibility values for each of the plurality of hypotheses, and selects a hypothesis having a highest support value;

such that a general purpose processor can execute the executable instructions stored on the computer readable medium to select a hypothesis for a given input from a plurality of available hypotheses.

11. A computer readable medium as set forth in claim 10 wherein the plurality of hypotheses include output classes associated with at least one recognizer.

12. A computer readable medium as set forth in claim 10 wherein the data fusion routine outputs a negative hypothesis, indicating that an appropriate hypothesis cannot be selected for the input, if the determined belief for the associated hypothesis fails to meet a threshold value and the uncertainty level is high.

13. A computer readable medium as set forth in claim 10 wherein a given recognizer produces a plurality of candidate outputs and ranks the candidate outputs according to associated output scores.

14. A system for classifying an input pattern into one of a plurality of output classes comprising:

a memory comprising executable instructions, the executable instructions comprising;

a plurality of pattern recognition routines, a given pattern recognition routine selecting at least one of the plurality of output classes and assigning respective output scores to the selected at least one output class;

at least one fuzzy class routine that assigns a fuzzy membership state to the selected output classes of the plurality of pattern recognition routines;

a rule selection routine that evaluates a plurality of rules according to the assigned fuzzy membership states to determine which of the plurality of rules apply to each of a plurality of output hypotheses, an applicable rule providing a determined amount of support mass for an associated hypothesis and a determined amount of uncertainty mass; and

a data fusion routine that multiplies the associated support masses for a plurality of selected rules associated with each hypothesis to form a support value for the hypothesis and multiplying the associated uncertainty mass for the plurality of selected rules associated with each hypothesis to form an uncertainty value for the hypothesis and selects an output class associated with a hypothesis having a highest support value; and

a processor for executing the executable instructions as to classify the input pattern into one of the plurality of output classes.

15. A system as set forth in claim 14 wherein the plurality of output class represent human faces.

16. A system as set forth in claim 14 wherein the plurality of pattern recognition routines includes a neural network classifier.

17. A system as set forth in claim 14 wherein the input pattern comprises a video input recording at least one entrant to a secured location.

18. A system as set forth in claim 17 wherein the classification system determines the identity of a given entrant to the secured location from the video input.

19. A system as set forth in claim 18 wherein the input image is analyzed relative to an entrant profile associated with the identified entrant to determine if an abnormal condition exists.

20. A system as set forth in claim 19, wherein the entrant profile includes the typical time of entry and place of entry by an entrant to the building.

21. A system as set forth in claim 19, wherein the entrant profile includes items typically carried by the entrant.

22. A system as set forth in claim 19, wherein the system includes an alarm that notifies a human operator when an abnormal condition exists.