# EXTRACTING CASE-BASED ANSWERS FROM CLOSED PROOF-TREES

### Isabel Gomes Barbosa, Newton José Vieira

#### Abstract

A question of the form “Find X such that P(X) is true” may produce in the most usual inference systems an answer that has the general form P(T1)∨P(T2)∨. . .∨P(Tk). If we have k ≥ 2, the answer is then termed a disjunctive answer. In some scenarios, a disjunctive answer of this form may be considered too imprecise to help the user in his activities. However, an answer which specifies the cases in which each element P(Ti) is true would be a perfectly appropriate answer to the question. In this paper, we propose an algorithm that, from a deduction of P(T1)∨P(T2)∨. . .∨P(Tk), k ≥ 2, on the form of a proof-tree, extracts a case-based answer to the exact same question. A case-based answer is an answer given in terms of a finite number of cases, each one implying a non-disjunctive answer P(Ti), 1 ≤ i ≤ k, to the user’s question.

#### References

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#### Paper Citation

#### in Harvard Style

Gomes Barbosa I. and José Vieira N. (2010). **EXTRACTING CASE-BASED ANSWERS FROM CLOSED PROOF-TREES** . In *Proceedings of the 2nd International Conference on Agents and Artificial Intelligence - Volume 1: ICAART,* ISBN 978-989-674-021-4, pages 377-384. DOI: 10.5220/0002736703770384

#### in Bibtex Style

@conference{icaart10,

author={Isabel Gomes Barbosa and Newton José Vieira},

title={EXTRACTING CASE-BASED ANSWERS FROM CLOSED PROOF-TREES},

booktitle={Proceedings of the 2nd International Conference on Agents and Artificial Intelligence - Volume 1: ICAART,},

year={2010},

pages={377-384},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0002736703770384},

isbn={978-989-674-021-4},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 2nd International Conference on Agents and Artificial Intelligence - Volume 1: ICAART,

TI - EXTRACTING CASE-BASED ANSWERS FROM CLOSED PROOF-TREES

SN - 978-989-674-021-4

AU - Gomes Barbosa I.

AU - José Vieira N.

PY - 2010

SP - 377

EP - 384

DO - 10.5220/0002736703770384