Pandora: A Reasoning Toolbox using Natural Deduction Style

Pandora is a tool for supporting the learning of first ordernatural deduction. It includes a help window, an interactivecontext sensitive tutorial known as the "e-tutor" and facilitiesto save, reload and export to LATEX. Every attempt to applya natural deduction rule is met with either success or a helpfulerror message, providing the student with instant feedback.Detailed electronic logs of student usage are recorded for evaluationpurposes. This paper describes the basic functionality, thee-tutor, our experiences of using the tool in teaching and ourfuture plans.     

Open answer set programming for the semantic web

We extend answer set programming (ASP) with, possibly infinite, open domains. Since this leads to undecidable reasoning, we restrict the syntax of programs, while carefully guarding knowledge representation mechanisms such as negation as failure and inequalities. Reasoning with the resulting extended forest logic programs (EFoLPs) can be reduced to finite answer set programming, for which reasoners are available.We argue that extended forest logic programming is a useful tool for uniformly representing and reasoning with both ontological and rule-based knowledge, as they can capture a large fragment of the OWL DL ontology language equipped with DL-safe rules. Furthermore, EFoLPs enable nonmonotonic reasoning, a desirable feature in locally closed subareas of the Semantic Web.     

Termination of logic programs with imperfect information: applications and query procedure

A general logic programming framework allowing for the combination of several adjoint lattices of truth-values is presented. The language is sorted, enabling the combination of several reasoning forms in the same knowledge base. The contribution of the paper is two-fold: on the one hand, sufficient conditions guaranteeing termination of all queries for the fix-point semantics for a wide class of sorted multi-adjoint logic programs are presented and related to some well-known probability-based formalisms; in addition, we specify a general non-deterministic tabulation goal-oriented query procedure for sorted multi-adjoint logic programs over complete lattices. We prove its soundness and completeness as well as independence of the selection ordering. We apply the termination results to probabilistic and fuzzy logic programming languages, enabling the use of the tabulation proof procedure for query answering.     

任务情境和证据信息对青少年贝叶斯推理的影响研究

采用生活情境测查任务和经典测查任务探讨了任务情境对青少年贝叶斯推理的影响,以及生活情境测查任务中不同证据信息对青少年贝叶斯判断的影响作用.结果表明:(1)在生活情境测查任务中,从小学六年级到大学二年级,被试的贝叶斯推理能力稳步缓慢提升(相邻的两个被试组之间差异不显著,而不相邻的两个被试组之间差异更容易达到显著水平),发展没有出现加速期,而经典测查任务情境下没有表现出年龄差异;(2)贝叶斯推理作为条件概率的判断不仅受任务情境的影响,而且同一任务情境中不同证据信息也会影响贝叶斯判断.当证据信息与先验信念一致时,被试可以充分利用线索进行推理.     

The impact of object type on the spatial analogies in Korean preschoolers

We tested young children’s spatial reasoning in a match-to-sample task, manipulating the objects in the task (abstract geometric shapes, line drawings of realistic objects, or both). Korean 4- and 5-year-old children (N = 161) generalized the target spatial configuration (i.e., on, in, above) more easily when the sample used geometric shapes and the choices used realistic objects than the reverse (i.e., realistic-object sample to geometric-shape choices). With within-type stimuli (i.e., sample and choices were both geometric shapes or both realistic objects), 5-year-old, but not 4-year-old, children generalized the spatial relations more easily with geometric shapes than realistic objects. In addition, children who knew more locative terms (e.g., “in”, “on”) performed better on the task, suggesting a link to children’s spatial vocabulary. The results demonstrate an advantage of geometric shapes over realistic objects in facilitating young children’s performance on a match-to-sample spatial reasoning task.     

Diagnostic causal reasoning with verbal information

In diagnostic causal reasoning, the goal is to infer the probability of causes from one or multiple observed effects. Typically, studies investigating such tasks provide subjects with precise quantitative information regarding the strength of the relations between causes and effects or sample data from which the relevant quantities can be learned. By contrast, we sought to examine people’s inferences when causal information is communicated through qualitative, rather vague verbal expressions (e.g., “X occasionally causes A”). We conducted three experiments using a sequential diagnostic inference task, where multiple pieces of evidence were obtained one after the other. Quantitative predictions of different probabilistic models were derived using the numerical equivalents of the verbal terms, taken from an unrelated study with different subjects. We present a novel Bayesian model that allows for incorporating the temporal weighting of information in sequential diagnostic reasoning, which can be used to model both primacy and recency effects. On the basis of 19,848 judgments from 292 subjects, we found a remarkably close correspondence between the diagnostic inferences made by subjects who received only verbal information and those of a matched control group to whom information was presented numerically. Whether information was conveyed through verbal terms or numerical estimates, diagnostic judgments closely resembled the posterior probabilities entailed by the causes’ prior probabilities and the effects’ likelihoods. We observed interindividual differences regarding the temporal weighting of evidence in sequential diagnostic reasoning. Our work provides pathways for investigating judgment and decision making with verbal information within a computational modeling framework.     

Motivated reasoning in the prediction of sports outcomes and the belief in the “hot hand”

The present paper explores the role of motivation to observe a certain outcome in people’s predictions, causal attributions, and beliefs about a streak of binary outcomes (basketball scoring shots). In two studies we found that positive streaks (points scored by the participants’ favourite team) lead participants to predict the streak’s continuation (belief in the hot hand), but negative streaks lead to predictions of its end (gambler’s fallacy). More importantly, these wishful predictions are supported by strategic attributions and beliefs about how and why a streak might unfold. Results suggest that the effect of motivation on predictions is mediated by a serial path via causal attributions to the teams at play and belief in the hot hand.     

The modulation of disjunctive assertions

The theory of mental models postulates that disjunctions of the sort, A or B, where A and B are sensible everyday clauses, have a core meaning that allows an inclusive interpretation, referring to three possibilities: A and not-B, not-A and B, and A and B. The meaning of the clauses and knowledge can modulate this meaning by blocking the construction of at least one model of a possibility—for example, “Rui is playing tennis or he is surfing” blocks the model of Rui doing both activities. This theory is implemented in a computer program. Three experiments investigated the core interpretation and interpretations in which the contents of the clauses should block the model of A and B (as in the preceding example), the model of A and not-B, or the model of not-A and B. In Experiment 1, the participants listed the possibilities for each of the four sorts of disjunction. The results corroborated the predicted modulations. In Experiment 2, these predicted interpretations governed the conclusions that participants accepted from disjunctions and categorical premises. In Experiment 3, the predicted interpretations yielded reliable effects on the conclusions that the participants drew for themselves. We relate these results to theories of reasoning.     

Advice conditionals about tips and warnings: interpretations and inferences

Two experiments examine how people interpret and reason about advice conditionals, such as tips, for example, “if you study more your grades will improve”, and warnings, for example, “if you stop exercising you will gain weight”. Experiment 1 showed that when participants reason about whether a tip or warning could be true in different situations, their judgments correspond to a biconditional or conditional interpretation on about half of all trials, but to an enabling or tautology interpretation on many others. Experiment 2 showed that participants make few modus ponens and tollens inferences from tips and warnings, and more modus ponens inferences from tips than warnings. The implications for alternative theories are discussed.     

Does Environmental Experience Shape Spatial Cognition? Frames of Reference Among Ancash Quechua Speakers (Peru)

Previous studies have shown that language contributes to humans' ability to orient using landmarks and shapes their use of frames of reference (FoRs) for memory. However, the role of environmental experience in shaping spatial cognition has not been investigated. This study addresses such a possibility by examining the use of FoRs in a nonverbal spatial memory task among residents of an Andean community in Peru. Participants consisted of 97 individuals from Ancash Quechua‐speaking households (8–77 years of age) who spoke Quechua and/or Spanish and varied considerably with respect to the extent of their experience in the surrounding landscape. The results demonstrated that environmental experience was the only factor significantly related to the preference for allocentric FoRs. The study thus shows that environmental experience can play a role alongside language in shaping habits of spatial representation, and it suggests a new direction of inquiry into the relationships among language, thought, and experience.