Probability, logic and the cognitive foundations of rational belief

Since Pascal introduced the idea of mathematical probability in the 17th century discussions of uncertainty and “rational” belief have been dogged by philosophical and technical disputes. Furthermore, the last quarter century has seen an explosion of new questions and ideas, stimulated by developments in the computer and cognitive sciences. Competing ideas about probability are often driven by different intuitions about the nature of belief that arise from the needs of different domains (e.g., economics, management theory, engineering, medicine, the life sciences etc). Taking medicine as our focus we develop three lines of argument (historical, practical and cognitive) that suggest that traditional views of probability cannot accommodate all the competing demands and diverse constraints that arise in complex real-world domains. A model of uncertain reasoning based on a form of logical argumentation appears to unify many diverse ideas. The model has precursors in informal discussions of argumentation due to Toulmin, and the notion of logical probability advocated by Keynes, but recent developments in artificial intelligence and cognitive science suggest ways of resolving epistemological and technical issues that they could not address.     

“以毒攻毒”与中西医结合研究

“以毒攻毒”是中医药学一个重要医理和治则。本文介绍了国内外有关“以毒攻毒”的研究进展,以及具有“以毒攻毒”特点的医药研究状况。特别是德国细菌学家贝林等,研制成功破伤风和白喉抗毒素。我国学者张亭栋教授与陈竺教授,继承发掘中药砒霜治疗世界性难治病—急性早幼粒细胞白血病,取得国际领先水平的科研成果等等,表明中西医结合研究是继承发展中医药学的有效方法和途径。     

How Regulatory Orientation and Feelings of Gratitude Shape Online Review Helpfulness

Online review helpfulness ratings are an important indicator of the impact of online reviews. Often times, helpfulness is explained in terms of observable qualities of online reviews that predict helpfulness ratings. This research proposes that focusing on the psychological processes that underlie helpfulness voting informs a better understanding of what shapes review helpfulness ratings. Specifically, because goal orientation influences information processing, consumers’ regulatory orientation interacts with review valence to determine review helpfulness. When review valence and regulatory orientation match, consumers are more likely to express helpfulness through voting. The findings show that this effect occurs at least in part because matching review valence and regulatory orientation instills feelings of gratitude towards the reviewer. As a consequence, consumers are more likely to reward the reviewer with a helpfulness vote to express their feeling of gratitude through actions. However, when reviewers actively state expectations of reciprocal behavior by readers, gratitude is reduced and so is the likelihood that a review receives a helpfulness vote. Evidence from five studies using review data and online experiments show support for these effects.     

Levels of modality for BDI Logic

The use of rational agents for modelling real world problems has both been heavily investigated and become well accepted, with BDI (Beliefs, Desires, and Intentions) Logic being a widely used architecture to represent and reason about rational agency. However, in the real world, we often have to deal with different levels of confidence in the beliefs we hold, desires we have, and intentions that we commit to. This paper extends our previous framework that integrated qualitative levels of beliefs, desires, and intentions into BDI Logic. We describe an expanded set of axioms and properties of the extended logic. We present a modular structure for the semantics which involves a non-normal Kripke type semantics that may be used for other agent systems. Further, we demonstrate the usefulness of our framework with a scheduling task example.     

NPOs in China: Some Issues Concerning Internet Communication

The characteristics of Internet communication enable political, social, and cultural participation from the grassroots not only because the platforms provided by the Internet are open to all and inherently interactive but also because users are able to maintain their anonymity. Although, in theory, Internet communication is well-suited to the purposes of non-profit organization(s) (NPO(s)), in practice, Chinese NPOs do not to take full advantages of the Internet because of their bureaucratic and elitist approach. However, many Chinese who were once passive observers have been transformed into active participants as a result of Internet communication. This is significant because a civil society in China can only be achieved by the efforts of agents, not observers. Internet users have been actively learning the goals of civil society and participating in civil and political activities on the Internet, while Chinese NPOs rarely use the medium for advocacy.

Agent deliberation in an executable temporal framework

Autonomous agents are not so difficult to construct. Constructing autonomous agents that will work as required is much harder. A clear way in which we can design and analyse autonomous systems so that we can be more confident that their behaviour is as required is to use formal methods. These can, in principle, allow us to exactly specify the behaviour of the agent, and verify that any implementation has the properties required. In addition to using a more formal approach, it is clear that problems of conceptualisation and analysis can be aided by the use of an appropriate abstraction.In this article we tackle one particular aspect of formal methods for agent-based systems, namely the formal representation and implementation of deliberation within agents. The key aspect here is simplicity. Agents are specified using a relatively simple temporal logic and are executed by directly interpreting such temporal formulae. Deliberation is captured by modifying the way in which execution handles its temporal goals. Thus, in this article we provide motivations, theoretical underpinnings, implementation details, correctness arguments, and comparisons with related work.     

A verification framework for agent programming with declarative goals

A long and lasting problem in agent research has been to close the gap between agent logics and agent programming frameworks. The main reason for this problem of establishing a link between agent logics and agent programming frameworks is identified and explained by the fact that agent programming frameworks have hardly incorporated the concept of a declarative goal. Instead, such frameworks have focused mainly on plans or goals-to-do instead of the end goals to be realised which are also called goals-to-be. In this paper, the programming language GOAL is introduced which incorporates such declarative goals. The notion of a commitment strategy—one of the main theoretical insights due to agent logics, which explains the relation between beliefs and goals—is used to construct a computational semantics for GOAL. Finally, a proof theory for proving properties of GOAL agents is introduced. Thus, the main contribution of this paper, rather than the language GOAL itself, is that we offer a complete theory of agent programming in the sense that our theory provides both for a programming framework and a programming logic for such agents. An example program is proven correct by using this programming logic.     

Visual memory for agents and their actions

Humans spend a considerable amount of time remembering other individuals' actions. Nevertheless, it is unclear how the visual system stores information about the identities of agents and their actions. To address this, I used a change detection method where observers were asked to remember agents and the actions they performed. Results show that observers can maintain information about both 2-3 agents and 2-3 actions simultaneously. However, they are highly impaired for remembering which agent performed which action, indicating that agent and action information are retained separately in visual working memory. Further experiments show that agent and action information can be bound together when the visual input contains the appropriate cues. However, this binding process significantly reduces the total amount of information that can be retained. Together, these results show that (1) an additional, resource-demanding process is needed to integrate agent and action information stored in separate working memory stores, and (2) the extent to which these two types of information are bound into integrated units depends largely on the presence of specific cues in the visual input.     

Calculating the attentional orientation of an unfamiliar agent in infancy

By the end of the first year, infants are able to recognize both goal-directed and perceptually guided behavior in the actions of non-human agents, even faceless ones. How infants derive the relevant orientation of an unfamiliar agent in the absence of familiar markers such as eyes, ears, or face is unknown. The current studies tested the hypothesis that infants’ calculate an agent's “front” from the geometry of its behavior in the spatial environment. In the first study, 14–15-month-old infants observed a symmetrical, faceless agent either interact contingently with a confederate or act randomly. It then turn toward one of two target objects. Infants were more likely to look in the direction the agent turned than the opposite direction, but only in the contingent condition. In the second study, the location of the confederate and target objects was varied, which in turn influenced which end of the agent infants interpreted as the front. Finally, implications for infants’ early gaze-following behaviors with humans are tested and implications for theory of mind development more broadly are discussed.