The Consistency Argument for Ranking Functions

The paper provides an argument for the thesis that an agent’s degrees of disbelief should obey the ranking calculus. This Consistency Argument is based on the Consistency Theorem. The latter says that an agent’s belief set is and will always be consistent and deductively closed iff her degrees of entrenchment satisfy the ranking axioms and are updated according to the ranktheoretic update rules. Special Issue Formal Epistemology I. Edited by Branden Fitelson     

Automatic optimism: Biased use of base rate information for positive and negative events

People generally judge that positive events will occur in their lives and negative events will not, even when both events have the same objective likelihood to occur. In four studies, we examined the possibility that this optimistic bias is the result of people’s automatic affective reactions to future events. Studies 1 and 2 demonstrate, in two different contexts, that people are consistently optimistic in their predictions, despite identical base rates for positive and negative events. In Study 2, optimistic bias was not influenced by incentives for motivated reasoning or rewards for accuracy, suggesting that bias was the result of automatic processes. Studies 3 and 4 showed that optimistic bias was more pronounced when predictions were speeded and when participants made predictions after exposure to affectively valenced words. Together, these findings suggest that people optimistically interpret base rates and that this optimism is due to an effortless affective process.     

Comparing Inductive and Circular Definitions: Parameters,Complexity and Games

Gupta-Belnap-style circular definitions use all real numbers as possible starting points of revision sequences. In that sense they are boldface definitions. We discuss lightface versions of circular definitions and boldface versions of inductive definitions.     

WISC-IV GAI and CPI profiles in healthy children and children with learning disabilities

IntroductionIn addition to the FSIQ, the General Ability Index (GAI) and the Cognitive Proficiency Index (CPI) are two ancillary scores that can be calculated for the Wechsler Intelligence Scale. The GAI and the CPI have been proposed to assist in identifying cognitive strengths and weaknesses, and thus to provide different views into individual's cognitive abilities.ObjectiveThe purpose of the present study is to provide the frequency of GAI/CPI score difference by direction, the frequency of FSIQ/GAI score difference, and the frequency of FSIQ/CPI score difference, for the French Wechsler Intelligence Scale for Children and Adolescents–Fourth Edition (WISC-IV).MethodThese frequencies are provided for a sample of healthy children (n = 483), and for a sample of children with learning disabilities (LD, n = 370). The GAI comprises verbal comprehension and perceptual reasoning subtests, while CPI comprises working memory and processing speed subtests.ResultsResults indicated that the healthy sample performed better than the LD sample for all composite scores. The FSIQ was lower than the GAI for both groups and this difference was slightly larger for the LD sample (−1.35 points vs. −3.22 points). The GAI was higher than the CPI for both samples, but this difference was not significantly larger for the LD sample (4.2 points vs. 6.16 points). Finally, while the FSIQ was higher than the CPI for both groups, this difference was not larger for the LD sample (2.85 points vs. 2.95 points).ConclusionThese findings support the use of the GAI and the CPI, in addition to the FSIQ.     

Keeping the reader's mind in mind: Development of perspective-taking in children's dictations

This study investigated when children can take the perspective of their reader if the information-processing demands of writing are removed by means of dictation to a scribe. Participants (N = 96) aged 5, 6 and 7 years dictated letters to an addressee who possessed requisite content knowledge, and then revised the letter or dictated a new letter to an addressee who lacked this knowledge (counterbalanced). Results showed that 19% of 5-year-olds, 41% of 6-year-olds, and 72% of 7-year-olds considered their reader's missing knowledge. Children's awareness of their reader's knowledge was neither related to performance on higher-order theory of mind tasks, nor to measures of executive function. Significantly greater perspective-taking was demonstrated in children's new letters than revised letters. However, although revision is considered a late-developing skill, half of even the 5-year-olds were able to make revisions (albeit few revisions demonstrated actual perspective-taking). Findings have significant implications for the emergent-literacy curriculum.     

Unrealistic representations of “the self”: A cognitive neuroscience assessment of anosognosia for memory deficit

Three cognitive components may play a crucial role in both memory awareness and in anosognosia for memory deficit (AMD): (1) a personal data base (PDB), i.e., a memory store that contains “semantic” representations about the self, (2) monitoring processes (MPs) and (3) an explicit evaluation system (EES), or comparator, that assesses and binds the representations stored in the PDB with information obtained from the environment.We compared both the behavior and the functional connectivity (as assessed by resting-state fMRI) of AMD patients with aware patients and healthy controls. We found that AMD is associated with an impoverished PDB, while MPs are necessary to successfully update the PDB.AMD was associated with reduced functional connectivity within both the default-mode network and in a network that includes the left lateral temporal cortex, the hippocampus and the insula. The reduced connectivity between the hippocampus and the insular cortex was correlated with AMD severity.