Samy Sá

FLAP Journal 2025 Journal Article

Syntactic and Semantic Connections between Logic Programming and Argumentation Systems

• Samy Sá
• Wolfgang Dvořák
• Martin Caminada

Logic programming was one of the first formalisms to incorporate nonmonotonic reasoning and, as such, is the origin of many semantics for this type of reasoning. Many of the core argumentation systems, including Abstract Argumentation, Assumption-Based Argumentation and Abstract Dialectical Frameworks even find their historical roots in the logic programming literature, borrowing terminology, procedures, notation and semantics from this niche. In this article, we provide an overview of the connections between logic programming and a series of argumentation systems, focusing on the semantic perspective to find their relative expressive power. The systems we examine in detail include the ones we already mentioned, as well as Argumentation Frameworks with Sets of Attacking Arguments. In each case, we consider translations and find whether they preserve the semantics of their respective source and target formalism, under some of the most common semantics. For some of the cases where equivalence does not hold, we consider how to restore it. Apart from that, we also offer an overview of how some of these argumentation systems can be implemented using Answer-Set Programming and their specialized solvers.

FLAP Journal 2015 Journal Article

On the Difference between Assumytion-Based Argumentation and Abstract Argumentation.

• Martin Caminada
• Samy Sá
• João F. L. Alcântara
• Wolfgang Dvorák

AAMAS Conference 2013 Conference Paper

Deliberation About Preferences and Group Decisions

• Samy Sá

Our research consists of an approach to Group Decision Making in multiagent systems that is inspired by human interaction. The main goal of the thesis is to evaluate how engaging in deliberation can help a group of agents to improve their decisions. In order to achieve that, we proposed a model of preferences that allows arguing about them and a protocol of deliberation which is inherently collaborative, but where preferences play a role to render agents individual and collective opinions. Our next step is to find metrics to quantify the satisfaction of an agent towards a decision, so we can compare the decisions in our method against those provided by social choice methods.

AAMAS Conference 2013 Conference Paper

Preferences with Qualitative Thresholds and Methods for Individual and Collective Decisions

• Samy Sá
• João Alcântara

In this paper, we propose a way to model preferences so agents base their decisions on beliefs and can reason about such preferences. This connection allows agents to build arguments about their preferences or to explain decisions, and update preferences as they review beliefs. We also discuss how agents can reach decisions and the role played by preferences in deliberation towards collective decision situations.