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181.
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.  相似文献   
182.
Køppe’s proposition of four layers in theoretical building are used here in the exploration of a specific case of eclectic combination, the use of Piagetian and Vygotskian general approaches to the analysis of proportional reasoning as a cognitive mathematical ability. It is proposed here that the eclectic consideration of these contributions depends on the consideration of their specificity, in the sense that they highlight different aspects of the phenomenon under scrutiny, and also on the consideration of the coherence between this eclectic convergence and premises in terms of schools of thought under which each contribution is framed. We conclude proposing in accordance to S. Køppe’s proposal that eclecticism can be valuable and heuristic in theory development, but this contribution will depend largely on the effort in establishing careful relations between the four layers of theory-building.  相似文献   
183.
Analogical reasoning is considered the hallmark of human reasoning, but some studies have demonstrated that language- and symbol-trained chimpanzees can also reason analogically. Despite the potential adaptive value of this ability, evidence from other studies strongly suggests that other nonhuman primates do not have this capacity for analogical reasoning. In our three experiments, 6 of 29 baboons acquired the ability to perform a relational matching-to-sample (RMTS) task in which pairs of shapes composed relational displays. Five of these 6 monkeys then transferred this ability to RMTS tasks using novel exemplars of identity (elements in a pair are the same) and nonidentity (elements in a pair are different) relations. This transfer occurred even on trials in which the incorrect pair shared an element with the sample pair with which it was being compared. The baboons retained this ability 12 months later. The findings from our study of symbol-naive monkeys indicate that although language and symbol training facilitate conceptual thinking in nonhuman primates, such training is not a prerequisite for analogical reasoning.  相似文献   
184.
Perceivers generally show a poor ability to detect changes, a condition referred to as “Change Blindness” (CB). They are, in addition, “blind to their own blindness”. A common explanation of this “Change Blindness Blindness” (CBB) is that it derives from an inadequate, “photographical” folk-theory about perception. This explanation, however, does not account for intra-individual variations of CBB across trials. Our study aims to explore an alternative theory, according to which participants base their self-evaluations on two activity-dependent cues, namely search time and perceived success in prior trials. These cues were found to influence self-evaluation in two orthogonal ways: success-feedback influenced self-evaluation in a global, contextual way, presumably by recalibrating the norm of adequacy for the task. Search time influenced it in a local way, predicting the success of a given trial from its duration.  相似文献   
185.
We present the first steps in the validation of an observational tool for father-mother-infant interactions: the FAAS (Family Alliance Assessment Scales). Family-level variables are acknowledged as unique contributors to the understanding of the socio-affective development of the child, yet producing reliable assessments of family-level interactions poses a methodological challenge. There is, therefore, a clear need for a validated and clinically relevant tool. This validation study has been carried out on three samples: one non-referred sample, of families taking part in a study on the transition to parenthood (normative sample; n = 30), one referred for medically assisted procreation (infertility sample; n = 30) and one referred for a psychiatric condition in one parent (clinical sample; n = 15). Results show that the FAAS scales have (1) good inter-rater reliability and (2) good validity, as assessed through known-group validity by comparing the three samples and through concurrent validity by checking family interactions against parents’ self-reported marital satisfaction.  相似文献   
186.
Endocannabinoids (eCBs) modulate a variety of brain functions via activation of the widely expressed CB1 receptor. One site of high density of this receptor is the basolateral amygdala (BLA), a structure involved in the formation of aversive memories. The activation and blockade of CB1 receptors by systemic or hippocampal drug administrations have been shown to modify memory processing. However, little is known about the role of the BLA endocannabinoid system in aversive memories. Additionally, BLA endocannabinoid transmission seems to be related to emotional states, but the relevance of these effects to memory formation is still unknown. In this study we investigated the effects of the eCB anandamide (AEA) and the CB1 antagonist/inverse agonist AM251 infused into the BLA on the acquisition of an aversive memory task, concomitantly evaluating basal anxiety levels in rats. Male rats received pre-training micro-injection of AEA, AM251 or vehicle bilaterally into the BLA, and were studied with the plus-maze discriminative avoidance task (a paradigm that allows concomitant and independent evaluation of anxiety-like behavior and the memory of an aversive task). Our results showed that AEA into the BLA before training prevented memory retrieval 24 h later, as evaluated by exploration of the aversive arm of the maze, while AM251 into the BLA did not interfere with animals' performance. In addition, AEA had no effect on anxiety-like behavior (as evaluated by open arm exploration and risk assessment), while AM251 induced an anxiogenic effect. Our data indicate an important role of BLA CB1 receptors in aversive memory formation, and suggest that this involvement is not necessarily related to a possible modulation of anxiety states.  相似文献   
187.
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.  相似文献   
188.
The aim of this study was to analyze the relationship between personal values and well-being. Two correlational studies are presented with the following random samples: (1) four native samples: two samples from the 2006 European Social Survey (Europe n1 = 28,375, Spain n2 = 1,321) and two Basque samples (n3 = 1,770; n4 = 820); and (2) a sample of immigrants in the Basque Country (quasirandom) (n5 = 1,171). Age range of respondents was 18–60 years. The instruments used were for measuring: (1) personal values (Schwartz’s PVQ-40 or PVQ-21), and (2) well-being (Bradburn’s PNA, Goldberg’s GHQ, and life satisfaction and perceived control items from the World Value Survey). Partial correlation analysis was applied, with PVQ scale response bias controlled. The data supported a positive association of hedonic and psychological well-being with openness to experience and individualist values, and a negative association with power and conservation or collectivist values. Satisfaction with life partially mediated the relationship between personal values and affect. The results support a universal association of healthy values with well-being.  相似文献   
189.
We studied the efficacy and implementation outcomes of a culturally responsive parent training (PT) program. Fifty-four Chinese American parents participated in a wait-list controlled group randomized trial (32 immediate treatment, 22 delayed treatment) of a 14-week intervention designed to address the needs of high-risk immigrant families. Parents were eligible for intervention if they were Chinese-speaking immigrants referred from schools, community clinics, or child protective services with concerns about parenting or child behavior problems. Retention and engagement were high with 83% of families attending 10 or more sessions. Results revealed that the treatment was efficacious in reducing negative discipline, increasing positive parenting, and decreasing child externalizing and internalizing problems. Treatment effects were larger among families with higher levels of baseline behavior problems and lower levels of parenting stress. Further augmentation of PT to address immigrant parent stress may be warranted. Qualitative impressions from group leaders suggested that slower pacing and increased rehearsal of skills may improve efficacy for immigrant parents unfamiliar with skills introduced in PT.  相似文献   
190.
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.  相似文献   
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