An investigation of DIF mechanisms in the context of differential testlet effects

This study investigated differential item functioning (DIF) mechanisms in the context of differential testlet effects across subgroups. Specifically, we investigated DIF manifestations when the stochastic ordering assumption on the nuisance dimension in a testlet does not hold. DIF hypotheses were formulated analytically using a parametric marginal item response function approach and compared with empirical DIF results from a unidimensional item response theory approach. The comparisons were made in terms of type of DIF (uniform or non‐uniform) and direction (whether the focal or reference group was advantaged). In general, the DIF hypotheses were supported by the empirical results, showing the usefulness of the parametric approach in explaining DIF mechanisms. Both analytical predictions of DIF and the empirical results provide insights into conditions where a particular type of DIF becomes dominant in a specific DIF direction, which is useful for the study of DIF causes.     

Too much anticipation? Large anticipatory adjustments of grasping movements to minimal object manipulations

When humans grasp objects, the grasps foreshadow the intended object manipulation. It has been suggested that grasps are selected that lead to medial arm postures, which facilitate movement speed and precision, during critical phases of the object manipulation. In Experiment 1, it has been tested whether grasp selections lead to medial postures during rotations of a dial. Participants twisted their arms considerably before grasping the dial, even when the upcoming dial rotation was minimal (5°). Participants neither assumed a medial posture at any point during a short rotation, nor did they assume any of the postures involved in short rotations in the opposite direction. Thus, grasp selections did not necessarily lead to specific postures at any point of the object manipulation. Experiment 2 examined the effect of various grasps on the speed of dial rotations. A medial initial grasp resulted in the fastest dial rotations for most rotation angles. Spontaneously selected grasps were more excursed than necessary to maximize dial rotation speed. This apparent overshot might be explained by participants’ sensitive to the variability of their grasps and is in line with the assumption that grasps facilitate control over the grasped object.     

What is the Accordion Effect?

In "Action and Responsibility,' Joel Feinberg pointed to an important idea to which he gave the label "the accordion effect.' Feinberg's discussion of this idea is of interest on its own, but it is also of interest because of its interaction with his critique, in his "Causing Voluntary Actions,' of a much discussed view of H. L. A. Hart and A. M. Honoré that Feinberg labels the "voluntary intervention principle.' In this essay I reflect on what the accordion effect is supposed by Feinberg to be, on differences between Feinberg's understanding of this idea and that of Donald Davidson, and on the interaction between Feinberg's discussion of the accordion effect and his critique of the voluntary intervention principle.     

Recent experience affects the strength of structural priming

In two experiments, we explore how recent experience with particular syntactic constructions affects the strength of the structural priming observed for those constructions. The results suggest that (1) the strength of structural priming observed for double object and prepositional object constructions is affected by the relative frequency with which each construction was produced earlier in the experiment, and (2) the effects of relative frequency are not modulated by the temporal placement of the tokens of each construction within the experiment.     

Learned preference for a hedonically negative flavor is observed after pairings with positive post-ingestion consequences rather than with a palatable flavor

In two experiments, thirsty rats consumed a compound of sucrose and a non-preferred flavor. In Experiment 1, a conditioned preference was observed in the experimental group when animals were tested both thirsty and hungry, but not when they were tested just thirsty. Animals in the control group, which experienced the flavor and the sucrose unpaired, never showed a preference. Experiment 2 replicated the absence of a preference in the experimental group when rats were tested thirsty, but provided evidence that a flavor-taste association had been formed during training. After conditioning, sucrose was paired with LiCl in group Dev whereas it was unpaired in group NonDev. The sucrose devaluation produced a decrease in CS preference in group Dev, and an increment in group NonDev. Taken together, these results show that preference for a non-preferred flavor can be readily observed after pairings with the positive consequences of the US (calories or absence of an expected illness) rather than with a palatable flavor.     

The Historical Effect of Habermas in the Chinese Context: A Case Study of the Structural Transformation of the Public Sphere

The main purpose of this essay is not to give a full-scale and systematic exploration of the historical process concerning the acceptance of Habermas’ works in the Chinese-spoken world but to examine the historical effect of Habermas in the Chinese-spoken context and try to find a proper way to establish a good relationship between Habermas and the Chinese-spoken world by discussing the introduction, study, and application of Habermas’ most famous work, The Structural Transformation of the Public Sphere, by Chinese scholars in recent years. Translated from Xiandai zhexue, 2005:1     

汉语名词短语产生中的量词一致性效应

目前,语言产生领域的多数研究都集中在口语词语产生方面,许多研究者针对不同的语言系统的特色,对功能词进行了大量跨语言的研究。汉语量词是汉藏语系独有的功能词,本研究采用词图干扰范式,以名词短语和简单名词两种不同的图片命名任务,探讨了汉语量词的产生过程。实验结果发现,在名词短语命名任务下,存在量词的一致性效应;在名词命名的任务下,则不存在这种一致性效应。研究还发现语义干扰效应在两种不同命名任务下出现了分离。语义干扰效应只在命名名词的任务下出现,在命名名词短语的任务下未被发现。     

Continuum modeling of the reverse Hall–Petch effect in nanocrystalline metals under uniaxial tension: how many grains in a finite element model?

Owing to their very high strength, nanocrystalline metals have been extensively studied over the recent years. The direct Hall–Petch law, empirically proportioning the material strength to the inverse square root of its grain size has been shown to break down below a grain size of the order of tenths of nanometers. This phenomenon has been widely rationalized as a gradual switch from intragrain mediated deformation mechanisms to grain boundary mediated deformation mechanisms. This transition has been observed in many finite element simulations, despite the intrinsic restriction of necessarily limiting the nanocrystalline representative assembly to only a few grains. Such a limitation is generally overlooked, and its influence on an uniaxial tension test – when compared to a complete sample of millions of grains – ignored. We propose here to quantify the approximation done by considering a finite number of grains by means of a simple analytical model based on the early work of Stevens [R.N. Stevens, Philos. Mag. 23 (1971) p. 265]. The finite element approximation is demonstrated to be relatively good, even down to only three grains in width, and a method to “correct” the stress-strain curves of small representative volumes is proposed.     

Understanding scale-dependent yield stress of metals at micrometre scales

The mechanical softening behaviour of micrometre-scale metals (free-standing metal foils and wires) with decreasing either the geometrical or the microstructural scale (i.e. the smaller, the weaker) has recently been reported. Here, we present a mechanism-based model to understand the softening behaviour, which is based on competition between the effects of surface grain relaxation and the interior grain strengthening effect. The model describes well the yield stress of Cu foils with different ratios of the thickness to grain size.