A logic of comparative obligation

Normal systems of modal logic, interpreted as deontic logics, are unsuitable for a logic of conflicting obligations. By using modal operators based on a more complex semantics, however, we can provide for conflicting obligations, as in [9], which is formally similar to a fragment of the logic of ability later given in [2], Having gone that far, we may find it desirable to be able to express and consider claims about the comparative strengths, or degrees of urgency, of the conflicting obligations under which we stand. This paper, building on the formalism of the logic of ability in [2], provides a complete and decidable system for such a language.     

Cut-Elimination and a Permutation-Free Sequent Calculus for Intuitionistic Logic

We describe a sequent calculus, based on work of Herbelin, of which the cut-free derivations are in 1-1 correspondence with the normal natural deduction proofs of intuitionistic logic. We present a simple proof of Herbelin's strong cut-elimination theorem for the calculus, using the recursive path ordering theorem of Dershowitz.     

Nonparametric item response theory axioms and properties under nonlinearity and their exemplification with knowledge space theory

This paper investigates the dichotomous Mokken nonparametric item response theory (IRT) axioms and properties under incomparabilities among latent trait values and items. Generalized equivalents of the unidimensional nonparametric IRT axioms and properties are formulated for nonlinear (quasi-ordered) person and indicator spaces. It is shown that monotone likelihood ratio (MLR) for the total score variable and nonlinear latent trait implies stochastic ordering (SO) of the total score variable, but may fail to imply SO of the nonlinear latent trait. The reason for this and conditions under which the implication holds are specified, based on a new, simpler proof of the fact that in the unidimensional case MLR implies SO. The approach is applied in knowledge space theory (KST), a combinatorial test theory. This leads to a (tentative) Mokken-type nonparametric axiomatization in the currently parametric theory of knowledge spaces. The nonparametric axiomatization is compared with the assumptions of the parametric basic local independence model which is fundamental in KST. It is concluded that this paper may provide a first step toward a basis for a possible fusion of the two split directions of psychological test theories IRT and KST.     

Mental architectures with selectively influenced but stochastically interdependent components

The way external factors influence distribution functions for the overall time required to perform a mental task (such as responding to a stimulus, or solving a problem) may be informative as to the underlying mental architecture, the hypothetical network of interconnected processes some of which are selectively influenced by some of the external factors. Under the assumption that all processes contributing to the overall performance time are stochastically independent, several basic results have been previously established. These results relate patterns of response time distribution functions produced by manipulating external factors to such questions as whether the hypothetical constituent processes in the mental architecture enter AND gates or OR gates, and whether pairs of processes are sequential or concurrent. The present study shows that all these results are also valid for stochastically interdependent component times, provided the selective dependence of these components upon external factors is understood within the framework of a recently proposed theory of selective influence. According to this theory each component is representable as a function of three arguments: the factor set selectively influencing it, a component-specific source of randomness, and a source of randomness shared by all the components.     

The Indirect Effect of Teachers’ Creative Mindsets on Teaching Creativity

Understanding how teachers’ implicit beliefs promote and inhibit students’ creativity has important implications for fostering creativity in the classroom. This study investigated whether the effect of teachers’ fixed creative mindset on their self‐efficacy for teaching creativity was mediated by their perceptions of students’ potential and the degree to which this indirect effect varied by level of growth creative mindset. A sample of educators (N = 119) completed an online survey containing questions regarding creative mindsets, perceptions of students’ potential, self‐efficacy for teaching creativity, and a set of relevant covariates. A moderated mediation analysis indicated that the more teachers believed creativity to be innate, the less teachers tended to perceive every student to possess creative potential. Consequently, teachers’ confidence in their ability to teach for creativity was diminished. Results from the corresponding tests of simple indirect effects indicated that this negative indirect effect of a fixed creative mindset was lessened by teachers’ growth creative mindset. Taken together, the findings suggest the likely significant role of teachers’ fixed and growth creative mindsets for fostering creativity in classroom.     

目标预知对路径整合的影响

本研究采用头盔式虚拟现实与返回起点或路标的路径完成任务, 通过指导语来调控被试对于返回位置的预知, 检验目标预知对人类路径整合的影响。实验结果表明, 对于返回起点这一目标的预知可以使被试有效地忽略由于路标出现或路标数量增加而导致的干扰, 而对于返回路标这一目标的预知程度越高, 可以促使被试做出更准确的反应。这样的结果体现了目标预知作为一种非感知觉因素对于人类路径整合的影响, 也体现了人类路径整合的策略性和灵活性。     

人类路径整合的心理机制与神经基础

路径整合是指巡航者对与自身运动有关的信息进行整合来完成巡航任务的过程。这些与自身运动有关的信息可以是内源性的,如前庭感觉、本体感觉、动作指令的信息;也可以是外源性的,如视觉流。路径整合在许多物种中存在。人类路径整合的行为实验表明,以自我为参照系的空间表征和以环境为参照系的空间表征都有可能支持路径整合。神经科学的研究则表明,海马、内嗅皮层等内侧颞叶区域和以楔前叶等顶叶区域都与人类路径整合密切相关。     

高中生学习力的影响因素研究*

采用自编学习力及学习力影响因素问卷,对3056名高中生进行调查,建构学习力与影响因素的数学模型,探究各影响因素对高中生学习力的影响路径。结果发现,（1）影响高中生学习力的因素有六个,分别是认知能力、动机水平、精神状态、人际协调、身心优势感和学习氛围。（2）对学习力解释的贡献率大小排列依次为：精神状态、动机水平、学习氛围、认知能力、身心优势感和人际协调。（3）学习方法运用力主要受动机水平、精神状态、学习氛围、认知能力等4因素的影响;学习态度调控力主要受到精神状态、动机水平、学习氛围及认知能力等4因素的影响;学习自控力主要受精神状态的影响;提问互惠力主要受认知能力、精神状态、动机水平及学习氛围的影响。     

结构方程模型的应用及分析策略

差不多所有心理、教育、社会等概念,均难以直接准确测量,结构方程（SEM,Struc－tulalEquationModelling）提供一个处理测量误差的方法,采用多个指标去反映潜在变量,也令估计整个模型因子间关系,较传统回归方法更为准确合理。本文主要用一系列有关学习动机的虚拟例子,指出每个问题的主要分析策略,以展示SEM在教育及心理学可以应用的研究范畴。文内探讨的方法包括：验证性因素、高阶因子、路径及因果分析、多时段（multiwave）设计、单形模型（SimpleModel）、及多组比较等。     

Vacancy-mediated structural changes in Au–Cu nanoparticles

We report the formation of new phases in bimetallic Au–Cu nanoparticles. These phases were observed in nanoparticle synthesised by adopting a three-step protocol in a single pot. Nanoparticles at 180°C for 1?h led to the formation of single-phase solid solution of Cu in Au. Subsequent heat treatment at 290°C for 2?h of these Au–Cu nanoparticles revealed three new phases. One of them relates to the modification of occupancy of Cu in an ordered AuCu tetragonal phase (tP4). This cell although retains tetragonal symmetry but displays metrical properties akin to that of a cube. The other two relates to vacancy ordering along <111> directions in the {111} planes of an ordered AuCu3 cubic phase (cP4). On the one hand, statistical occupancy of vacancy on Cu site in this cell leads to the reduction of cell size from ～3.75?Å to ～3.5?Å whereas ordering of vacant layer on the other hand gives rise to symmetry breaking. Former continues to display cubic symmetry whereas latter transforms to a trigonal cell.