Abductive inference in defeasible reasoning: a model for research programmes

Abduction is regarded as the inference process that goes from observations to explanations within a more general context or theoretical framework. There are good characterizations of abduction of surprising observations in monotonic theories. Also, in normal logic programs there are a tight relation among SLDNF and the abduction of negative literals. However, a problem that faces abduction is the explanation of anomalous observations, i.e., observations that are contradictory with respect to the current theory. For this reason, in this work we will consider the problem of embedding abduction of surprising and anomalous observations in defeasible (nonmonotonic) theories. We discuss some issues arising the pragmatic acceptance of abductive inferences in defeasible theories, and how to accommodate anomalous observations and characterize all the possible outcomes that a defeasible theory may face when confronted with new evidence. We explore the use of partial structures approach as a semantic foundation for our system. Finally, we discuss an application of our system as a formal device for representing the methodology of scientific research programmes. In this representation, a programme is regarded as a defeasible theory that draws predictions. When confronted with surprising or anomalous observations, the programme protects itself by means of heuristic procedures, which are represented in our system as abductive inference procedures.     

Some Thoughts on A. H. Louie’s “More Than Life Itself: A Reflection on Formal Systems and Biology”

We review and discuss A. H. Louie’s book “More than Life Itself: A Reflexion on Formal Systems and Biology” from an interdisciplinary viewpoint, involving both biology and mathematics, taking into account new developments and related theories.     

The contribution of personality traits and self‐efficacy beliefs to academic achievement: A longitudinal study

Background. The personal determinants of academic achievement and success have captured the attention of many scholars for the last decades. Among other factors, personality traits and self‐efficacy beliefs have proved to be important predictors of academic achievement. Aims. The present study examines the unique contribution and the pathways through which traits (i.e., openness and conscientiousness) and academic self‐efficacy beliefs are conducive to academic achievement at the end of junior and senior high school. Sample. Participants were 412 Italian students, 196 boys and 216 girls, ranging in age from 13 to 19 years. Methods. The hypothesized relations among the variables were tested within the framework of structural equation model. Results and conclusions. Openness and academic self‐efficacy at the age of 13 contributed to junior high‐school grades, after controlling for socio‐economic status (SES). Junior high‐school grades contribute to academic self‐efficacy beliefs at the age of 16, which in turn contributed to high‐school grades, over and above the effects of SES and prior academic achievement. In accordance with the posited hypothesis, academic self‐efficacy beliefs partially mediated the contribution of traits to later academic achievement. In particular, conscientiousness at the age of 13 affected high‐school grades indirectly, through its effect on academic self‐efficacy beliefs at the age of 16. These findings have broad implications for interventions aimed to enhance children's academic pursuits. Whereas personality traits represent stable individual characteristics that mostly derive from individual genetic endowment, social cognitive theory provides guidelines for enhancing students’ efficacy to regulate their learning activities.     

Checkmate? The role of gender stereotypes in the ultimate intellectual sport

Women are surprisingly underrepresented in the chess world, representing less that 5% of registered tournament players worldwide and only 1% of the world's grand masters. In this paper it is argued that gender stereotypes are mainly responsible for the underperformance of women in chess. Forty‐two male–female pairs, matched for ability, played two chess games via Internet. When players were unaware of the sex of opponent (control condition), females played approximately as well as males. When the gender stereotype was activated (experimental condition), women showed a drastic performance drop, but only when they were aware that they were playing against a male opponent. When they (falsely) believed to be playing against a woman, they performed as well as their male opponents. In addition, our findings suggest that women show lower chess‐specific self‐esteem and a weaker promotion focus, which are predictive of poorer chess performance. Copyright © 2007 John Wiley & Sons, Ltd.     

The turple effect is modulated by base word frequency: Implications for models of lexical and semantic access

People who are asked to classify whether words presented visually belong to the category of animals respond to nonwords derived from animal names more slowly than they do to nonwords derived from nonanimal names. This is known as the turple effect (Forster, 2006; Forster & Hector, 2002). In the present article, we show that the turple effect is modulated by the frequency of the animal names from which the nonwords are derived: In particular, we show that nonwords derived from high-frequency animal names are rejected faster than those derived from low-frequency animal names. We discuss the implications of this result for two approaches to lexical and semantic access modeling. 2008 Psychonomic Society, Inc.     

Categories and Facets in Integrative Levels

Facets and general categories used in bibliographic classification have been based on a disciplinary organization of knowledge. However, facets and categories of phenomena independent from disciplines can be identified similarly. Phenomena can be classified according to a series of integrative levels (layers), which in turn can be grouped into the major strata of form, matter, life, mind, society and culture, agreeing with Nicolai Hartmann’s ontology. Unlike a layer, a stratum is not constituted of elements of the lower ones; rather, it represents the formal pattern of the lower ones, like the horse hoof represents the shape of the steppe. Bibliographic categories can now be seen in the light of level theory: some categories are truly general, while others only appear at a given level, being the realization of a general category in the specific context of the level: these are the facets of that level. In the notation of the Integrative Level Classification project, categories and facets are represented by digits, and displayed in a Web interface with the help of colours.     

Teachers' self-efficacy beliefs as determinants of job satisfaction and students' academic achievement: A study at the school level

Teachers' self-efficacy beliefs were examined as determinants of their job satisfaction and students' academic achievement. Over 2000 teachers in 75 Italian junior high schools were administered self-report questionnaires to assess self-efficacy beliefs and their job satisfaction Students' average final grades at the end of junior high school were collected in two subsequent scholastic years. Structural equation modeling analyses corroborated a conceptual model in which teachers' personal efficacy beliefs affected their job satisfaction and students' academic achievement, controlling for previous levels of achievement.     

Neuroanatomical correlates of handedness for tool use in chimpanzees (Pan troglodytes): implication for theories on the evolution of language

It has been hypothesized that cognitive mechanisms underlying lateralized complex motor actions associated with tool use in chimpanzees may have set the stage for the evolution of left-hemisphere specialization for language and speech in humans. Here we report evidence that asymmetries in the homologues to Broca's and Wernicke's areas are associated with handedness for tool use in chimpanzees. These results suggest that the neural substrates of tool use may have served as a preadaptation for the evolution of language and speech in modern humans.     

Dysfunctional attitudes and episodes of major depression: Predictive validity and temporal stability in never-depressed, depressed, and recovered women

In a large, community-based sample of women (N = 750), the authors examined the nature of associations between dysfunctional attitudes and depression. Dysfunctional attitudes were evaluated both as a vulnerability factor for depression and as a consequence of depression. A link was found between past depression and baseline elevations in dysfunctional attitudes that was independent of current subsyndromal symptoms, but intensification of dysfunctional attitudes following prospectively evaluated episodes of depression (depressive "scarring") was not observed. Although baseline dysfunctional attitudes predicted an episode of major depression over 3 years of prospective study, this prediction, considered alone or in interaction with negative life events, was redundant with that offered by history of past depression. Further, no significant prediction was evident for the Dysfunctional Attitude Scale (A. N. Weissman & A. T. Beck, 1978) when the formerly depressed and never-depressed cohorts were considered separately. Implications for cognitive theories are discussed.     

Factorial invariance of the theory of planned behavior applied to physical activity across gender,age, and ethnic groups

Objectives:The present study assessed the generalizability of the Theory of Planned Behavior (TPB) applied to physical activity and to examine if the TPB operates equivalently across gender, age, and ethnic sub-groups.Design/Methods:Measurement equivalence was evaluated for gender (male/female), age (19–34/35–54/55+) and ethnicity (Japanese/Hawaiian or part Hawaiian/Filipino/White) in a random sample (n = 3533) using Multisample Structural Equation Modeling.Results:Measurement equivalence was found for all variables and for their intercorrelations. Of the 100 possible TPB variable relationships between groups, only 6 were significant. The differences were found in explained variances of physical activity.Conclusions:The findings indicate that TPB measures apply over a range of population sub-groups, and should be considered comprehensively when designing interventions.