Jia Tao

AAMAS Conference 2025 Conference Paper

Logic of Knowledge and Cognitive Ability

• Jia Tao
• Xinran Zhang

Along with the convenience brought by the increasing usage of autonomous systems, unexpected accidents happened. These accidents emphasize the need for autonomous systems to possess the ability to recognize potential hazards, effectively communicate these hazards to human operators, and facilitate retrospective analyses. This ability, including recognition, prejudgment, postanalysis, and reasoning, falls within the realm of cognitive ability, which is important in improving the safety and outcomes in the decision-making process of such systems. In this paper, we present a foundational step toward addressing the safety challenges involving the cognitive ability of artificial agents. We study the interplay between knowledge and the cognitive ability of intelligent agents. The main technical result is a sound and complete bimodal logical system that describes the interplay between the knowledge and cognitive ability modalities.

IJCAI Conference 2025 Conference Paper

Responsibility Gap in Collective Decision Making

• Pavel Naumov
• Jia Tao

The responsibility gap is a set of outcomes of a collective decision-making mechanism in which no single agent is individually responsible. In general, when designing a decision-making process, it is desirable to minimise the gap. The paper studies the class of mechanisms for which the gap is empty and proposes a concept of an elected dictatorship. It shows that, in a perfect information setting, the gap is empty if and only if the mechanism is an elected dictatorship. It also proves that in an imperfect information setting, the class of gap-free mechanisms is positioned strictly between two variations of the class of elected dictatorships.

IJCAI Conference 2021 Conference Paper

Two Forms of Responsibility in Strategic Games

• Pavel Naumov
• Jia Tao

The paper studies two forms of responsibility, seeing to it and being blamable, in the setting of strategic games with imperfect information. The paper shows that being blamable is definable through seeing to it, but not the other way around. In addition, it proposes a bimodal logical system that describes the interplay between the seeing to it modality and the individual knowledge modality.

AIJ Journal 2020 Journal Article

An epistemic logic of blameworthiness

• Pavel Naumov
• Jia Tao

AAAI Conference 2020 Conference Paper

Blameworthiness in Security Games

• Pavel Naumov
• Jia Tao

Security games are an example of a successful real-world application of game theory. The paper defines blameworthiness of the defender and the attacker in security games using the principle of alternative possibilities and provides a sound and complete logical system for reasoning about blameworthiness in such games. Two of the axioms of this system capture the asymmetry of information in security games.

IJCAI Conference 2020 Conference Paper

Knowing-How under Uncertainty (Extended Abstract)

• Pavel Naumov
• Jia Tao

Logical systems containing knowledge and know-how modalities have been investigated in several recent works. Independently, epistemic modal logics in which every knowledge modality is labeled with a degree of uncertainty have been proposed. This article combines these two research lines by introducing a bimodal logic containing knowledge and know-how modalities, both labeled with a degree of uncertainty. The main technical results are soundness, completeness, and incompleteness of the proposed logical system with respect to two classes of semantics.

AAAI Conference 2019 Conference Paper

Blameworthiness in Strategic Games

• Pavel Naumov
• Jia Tao

There are multiple notions of coalitional responsibility. The focus of this paper is on the blameworthiness defined through the principle of alternative possibilities: a coalition is blamable for a statement if the statement is true, but the coalition had a strategy to prevent it. The main technical result is a sound and complete bimodal logical system that describes properties of blameworthiness in one-shot games.

AIJ Journal 2019 Journal Article

Knowing-how under uncertainty

• Pavel Naumov
• Jia Tao

AAMAS Conference 2018 Conference Paper

Second-Order Know-How Strategies

• Pavel Naumov
• Jia Tao

The fact that a coalition has a strategy does not mean that the coalition knows what the strategy is. If the coalition knows the strategy, then such a strategy is called a know-how strategy of the coalition. The paper proposes the notion of a second-order know-how strategy for the case when one coalition knows what the strategy of another coalition is. The main technical result is a sound and complete logical system describing the interplay between the distributed knowledge modality and the second-order coalition know-how modality.

AAAI Conference 2018 Conference Paper

Strategic Coalitions With Perfect Recall

• Pavel Naumov
• Jia Tao

The paper proposes a bimodal logic that describes an interplay between distributed knowledge modality and coalition know-how modality. Unlike other similar systems, the one proposed here assumes perfect recall by all agents. Perfect recall is captured in the system by a single axiom. The main technical results are the soundness and the completeness theorems for the proposed logical system.

AIJ Journal 2018 Journal Article

Together we know how to achieve: An epistemic logic of know-how

• Pavel Naumov
• Jia Tao

AAMAS Conference 2017 Conference Paper

Coalition Power in Epistemic Transition Systems

• Pavel Naumov
• Jia Tao

The paper proposes a bimodal logic that describes an interplay between coalition strategies and distributed knowledge. Unlike the existing literature, the paper assumes that a strategy must be not only executable but also verifiable. That is, the strategy of a coalition should be based only on the information distributively known by the coalition and the coalition must be able to verify the result after the strategy is executed. The main technical result of the paper is a sound and complete logical system describing all universal properties expressible in the proposed bimodal language. CCS Concepts •Theory of computation → Modal and temporal logics; •Computing methodologies → Reasoning about belief and knowledge; Multi-agent systems; Cooperation and coordination; Theory of mind;