Axiomatizations with Context Rules of Inference in Modal Logic

A certain type of inference rules in (multi-) modal logics, generalizing Gabbay's Irreflexivity rule, is introduced and some general completeness results about modal logics axiomatized with such rules are proved.     

Three Models of Sequential Belief Updating on Uncertain Evidence

Jeffrey updating is a natural extension of Bayesian updating to cases where the evidence is uncertain. But, the resulting degrees of belief appear to be sensitive to the order in which the uncertain evidence is acquired, a rather un-Bayesian looking effect. This order dependence results from the way in which basic Jeffrey updating is usually extended to sequences of updates. The usual extension seems very natural, but there are other plausible ways to extend Bayesian updating that maintain order-independence. I will explore three models of sequential updating, the usual extension and two alternatives. I will show that the alternative updating schemes derive from extensions of the usual rigidity requirement, which is at the heart of Jeffrey updating. Finally, I will establish necessary and sufficient conditions for order-independent updating, and show that extended rigidity is closely related to these conditions.     

Entailment with Near Surety of Scaled Assertions of High Conditional Probability

An assertion of high conditional probability or, more briefly, an HCP assertion is a statement of the type: The conditional probability of B given A is close to one. The goal of this paper is to construct logics of HCP assertions whose conclusions are highly likely to be correct rather than certain to be correct. Such logics would allow useful conclusions to be drawn when the premises are not strong enough to allow conclusions to be reached with certainty. This goal is achieved by taking Adams" (1966) logic, changing its intended application from conditionals to HCP assertions, and then weakening its criterion for entailment. According to the weakened entailment criterion, called the Criterion of Near Surety and which may be loosely interpreted as a Bayesian criterion, a conclusion is entailed if and only if nearly every model of the premises is a model of the conclusion. The resulting logic, called NSL, is nonmonotonic. Entailment in this logic, although not as strict as entailment in Adams" logic, is more strict than entailment in the propositional logic of material conditionals. Next, NSL was modified by requiring that each HCP assertion be scaled; this means that to each HCP assertion was associated a bound on the deviation from 1 of the conditional probability that is the subject of the assertion. Scaling of HCP assertions is useful for breaking entailment deadlocks. For example, it it is known that the conditional probabilities of C given A and of ¬ C given B are both close to one but the bound on the former"s deviation from 1 is much smaller than the latter"s, then it may be concluded that in all likelihood the conditional probability of C given A B is close to one. The resulting logic, called NSL-S, is also nonmonotonic. Despite great differences in their definitions of entailment, entailment in NSL is equivalent to Lehmann and Magidor"s rational closure and, disregarding minor differences concerning which premise sets are considered consistent, entailment in NSL-S is equivalent to entailment in Goldszmidt and Pearl"s System-Z ⁺. Bacchus, Grove, Halpern, and Koller proposed two methods of developing a predicate calculus based on the Criterion of Near Surety. In their random-structures method, which assumed a prior distribution similar to that of NSL, it appears possible to define an entailment relation equivalent to that of NSL. In their random-worlds method, which assumed a prior distribution dramatically different from that of NSL, it is known that the entailment relation is different from that of NSL.     

预期推理在长时记忆中的表征形式

该研究采用移动窗口技术,通过两个实验研究探讨在高低不同竞争条件下预期推理结果在长时记忆中的表征形式。实验结果表明,预期推理在长时记忆中的表征形式依赖于文本中预期推理的引发语境,在不同竞争强度的预期语境中,预期推理的结果在长时记忆会以不同的形式进行表征。在低竞争条件下,预期推理的结果以确定的形式表征;只有在高竞争条件下,预期推理的结果才会以假定的形式进行表征。     

The Revival of Rejective Negation

Whether assent (acceptance) and dissent (rejection) are thought of as speech acts or as propositional attitudes, the leading idea of rejectivism is that a grasp of the distinction between them is prior to our understanding of negation as a sentence operator, this operator then being explicable as applying to A to yield something assent to which is tantamount to dissent from A. Widely thought to have been refuted by an argument of Frege"s, rejectivism has undergone something of a revival in recent years, especially in writings by Huw Price and Timothy Smiley. While agreeing that Frege"s argument does not refute the position, we shall air some philosophical qualms about it in Section 5, after a thorough examination of the formal issues in Sections 1–4. This discussion draws on – and seeks to draw attention to – some pertinent work of Kent Bendall in the 1970s.     

文本阅读中预期推理激活与编码的语境条件研究

本研究通过三个实验考察了语义联系和因果制约对文本阅读中预期推理激活和编码的贡献。结果表明,预期语境与预期事件间的语义联系不能使预期推理在文本阅读过程中得到激活和编码,语境与预期事件间的强因果关系是文本阅读过程中预期推理激活与编码的必要条件;提示阅读过程中的预期是因果预期而非联想预期。结果为建构主义推理观提供了实验依据。     

含有新算符的代数运算规则学习的有效样例设计

为了探索含有新算符的代数运算规则学习的有效样例设计方式,分别采用“转换标记法”和“解释法”设计“指-对数转换”运算和对数运算的样例,考察了初中三年级学生代数运算规则样例学习的迁移效果。结果显示：(1)采用“转换标记法”设计的样例可以明显提高“指-对数转换”规则样例学习的迁移效果;(2)采用“解释法”设计的运算样例,能够明显促进“对数运算规则”的样例学习迁移效果,并与被试的基础知识有关。     

进化频率表征对统计推理（非）灵活性的影响：认知风格和简要提示不影响贝叶斯推理

当形式操纵有助于贝叶斯推理时会有怎样的加工发生呢？一种观点认为自然取样的频率可以激发在其操作中具有相对特异性的特权表征系统。而与之相对的一种观点则认为,自然取样频率只是引发具有嵌套关系的更为普遍的加工的一种方式。比较两种观点,后者预示着只需要使用相当简要和直接的干预（如简单的指示）就能够促进推理的改善,而前者则意味着更为广泛的干预和/或更有洞见的理解才能改善推理。本研究表明,无论是短暂立即的干预,还是预存的表征偏向,抑或是表征的灵活性都不能促进被试的表现。另一方面,也有证据显示,频率论者的问题解释可以改善统计推理表现,而且有时还会增加其反应的信心。这些结果支持了特权表征系统观