Title :
Extending Dempster-Shafer theory to overcome counter intuitive results
Author :
Campos, Fabio ; De Souza, Fernando M Campello
Author_Institution :
CEFET, Recife, Brazil
fDate :
30 Oct.-1 Nov. 2005
Abstract :
A popular formalism to model someone´s degrees of belief is the Theory of Evidence, or Dempster-Shafer Theory. This theory provides a method for combining evidence from different sources without prior knowledge of their distributions. It is also possible to assign probability values to sets of possibilities rather than to single events only, and it is unnecessary to divide all the probability values among the events, once the remaining probability should be assigned to the environment and not to the remaining events, thus modeling more naturally certain classes of problems. However, it has some pitfalls caused by the non natural embodiment of the uncertainty in the results. In this paper we present a method of automatic embodiment of the uncertainty that overcomes the afore mentioned pitfalls, allowing the combination of evidence with higher degrees of conflict, and avoiding the excessive tendency toward the common possibility of otherwise disjoint hypotheses. This is accomplished by means of a new rule of combination of bodies of evidence that embodies in the numeric results the unknown belief and conflict among the evidence, naturally modeling the epistemic reasoning.
Keywords :
belief networks; inference mechanisms; probability; uncertainty handling; Dempster-Shafer theory; Theory of Evidence; belief networks; epistemic reasoning; probability; uncertainty handling; Atomic measurements; Bayesian methods; Counting circuits; Knowledge representation; Magnetic resonance; Probability distribution; Uncertainty;
Conference_Titel :
Natural Language Processing and Knowledge Engineering, 2005. IEEE NLP-KE '05. Proceedings of 2005 IEEE International Conference on
Print_ISBN :
0-7803-9361-9
DOI :
10.1109/NLPKE.2005.1598832