RP-DeLP: a weighted defeasible argumentation framework based on a recursive semantics

Formalisation and logical properties of the maximal ideal recursive semantics for weighted defeasible logic programming

“…In [2] we show that, in case of some circular dependences among arguments, the output of an RP-DeLP program may be not unique, that is, there may exist several pairs (Warr, Block) satisfying the above conditions for a given RP-DeLP program. The following example shows a circular relation among arguments involving strict knowledge.…”

“…In order to characterize such situations we proposed in [2] the RP-DeLP framework, a new warrant semantics for P-DeLP based on a general notion of collective (non-binary) conflict among arguments ensuring the three rationality postulates defined by Caminada and Amgoud.…”

“…The cycle of the graph expresses that (1) the warranty of p depends on a (possible) conflict with r; (2) the support of r depends on q (i.e., r is valid whenever q is warranted); (3) the warranty of q depends on a (possible) conflict with s; and (4) the support of s depends on p (i.e., s is valid whenever p is warranted). In [2] we analyze the problem of deciding the set of conclusions that can be ultimately warranted in RP-DeLP programs with multiple outputs. The usual skeptical approach would be to adopt the intersection of all possible outputs.…”

Weighted logics for artificial intelligence – an introductory discussion

“…However, it is likely that a uniform view of strength is not applicable here, since the strength of an argument may refer to the uncertainty pervading the pieces of information on which it is based [4,73,3] and on the reliability of the source(s) of the argument, as well as on the rhetoric form of the argument (e.g. its length); moreover the argument itself may refer to a gradual view of truth (when stating for instance that "the higher the fever the more certain the child should remain in bed").…”

A Survey of Artificial Intelligence Research at IIIA

“…We have significatively extended the argumentation framework of defeasible logic programming (DeLP) along two different axes: (1) by incorporating the treatment of possibilistic uncertainty at object level, allowing to stratify defeasible rules in a DeLP program according to their strength, and defining a new recursive semantics that avoids some undesired side effects of the original semantics based on dialectical trees (Alsinet et al 2014); (2) by defining a discrete temporal extension of DeLP for defeasible causal reasoning, and its deployment for multiagent collaborative planning (Pardo and Godo 2013). All these results have been achieved in collaboration with leading international researchers in the area of computational argumentation such as G. Simari and C. Chesñevar, as well as with T. Alsinet and R. Bejar.…”