Habituation to a stressor predicts adolescents' adiposity

Background and Objectives: Stress is associated with gains in adiposity. One factor that determines how much stress is experienced is how quickly an adolescent reduces responding (habituates) across repeated stressors. The purpose of this study was to determine the association of body mass index (BMI) percentile and the rate of habituation to a stressor. Design: Thirty-four adolescents completed anthropometric measures and a habituation protocol using a within study design. Methods: The habituation protocol measured the rate of decline in perceived stress and heart rate (HR) across four, two-minute serial subtraction trials. Results: Multivariate linear regression revealed the habituation rate of the HR predicted BMI percentile after adjusting for gender, socioeconomic status, and initial HR (β?=?17.2, p?Conclusions: Slower habituation to a laboratory stressor was associated with greater BMI percentiles in adolescents.     

材料的几何属性差异对3—7岁儿童分类标准影响的研究

以７３名３—７岁儿童为被试,通过变换分类材料的几何属性（形状或大小）的差异程度,采用自由分类方法,探讨材料差异程度的变换对儿童分类标准的影响。结果表明：３—７岁儿童的分类标准均受分类材料几何属性差异变化的影响。３岁儿童的分类标准几乎完全随分类材料的变换而改变;４—５岁儿童的分类标准主要表现为随分类材料的变换而改变;６—７岁儿童的分类标准虽然有随分类材料的变换而改变的趋势,但已经表现出比较稳定的按形状分类;５—６岁是儿童分类能力发展的质的飞跃阶段。     

On the Logical Positivists' Theory of Truth: The Fundamental Problem and a New Perspective

The present article purports to show that the protocol sentence debate, pursued by some leading members of the Vienna Circle in the mid-1930s, was essentially a controversy over the explanation and the real significance of the concept of truth. It is further shown that the fundamental issue underlying the discussions about the concept of truth was the relationship between form and content, as well as between logic/language and the world. R. Carnap was the philosopher who most explicitly and systematically attempted to come to grips with this problem. It is shown that the form-content distinction pervades the three most important phases of Carnap's philosophical development: the structuralist (in Der logische Aufbau der Welt), the syntactical and the semantical. His final semantical stance is essentially determined by the concept of linguistic frameworks. The article purports to demonstrate that this concept cannot be dispensed with in philosophy, but that Carnap failed to work out its ontological implications. Finally, the concept of an internal ontology is briefly delineated. This revised version was published online in August 2006 with corrections to the Cover Date.     

Rule-Consequentialism's Dilemma

This paper examines recent attempts to defend Rule-Consequentialism against a traditional objection. That objection takes the form of a dilemma, that either Rule-Consequentialism collapses into Act-Consequentialism or it is incoherent. Attempts to avoid this dilemma based on the idea that using RC has better results than using AC are rejected on the grounds that they conflate the ideas of a criterion of rightness and a decision procedure. Other strategies, Brad Hooker's prominent amongst them, involving the thought that RC need contain no overarching concern to maximize the good are acknowledged to avoid the original dilemma, but lead to further problems of motivating and justifying RC in the absence of such a concern. The paper argues that Hooker's attempt to deal with these problems by using a 'Reflective Equilibrium plus method is unsuccessful.     

A priori tests in repeated measures designs: Effects of nonsphericity

The validity conditions for univariate repeated measures designs are described. Attention is focused on the sphericity requirement. For av degree of freedom family of comparisons among the repeated measures, sphericity exists when all contrasts contained in thev dimensional space have equal variances. Under nonsphericity, upper and lower bounds on test size and power of a priori, repeated measures,F tests are derived. The effects of nonsphericity are illustrated by means of a set of charts. The charts reveal that small departures from sphericity (.97 <1.00) can seriously affect test size and power. It is recommended that separate rather than pooled error term procedures be routinely used to test a priori hypotheses.Appreciation is extended to Milton Parnes for his insightful assistance.     

Infants' sensitivity to differential luminance as information about depth

To what degree are young infants able to perceive differential shadowing and to what degree are they able to utilize this stimulus parameter as information about depth? Two habituation experiments were performed. In Experiment 1, a group of 5-month-old infants were habituated to a low frequency, vertical, and approximately sinusoidal luminance grating superimposed on a flat colored surface. This display induced stable 3-D perception in adult subjects. After habituation, the infants viewed two test displays at alternating trials. One was made up of real half cylinders matching the light distribution of the habituation display and the other was made up of a square wave grating of the same spatial frequency as in the habituation one. Adults perceived the latter display as flat. Results showed that both test displays were treated as new ones by the infants habituated to the sinusoidal grating. Experiment 2 was identical to Experiment 1, except that the subjects were 3 1/2-month-old. These infants treated the half cylinders as familiar and the square wave grating as new. The results indicate that infants at both age levels (3 1/2 and 5 months of age) were sensitive to the difference between sharp and gradual change in luminance which is a prerequisite for perceiving form from luminance. However, neither age group seemed to utilize gradual change in luminance as information about space.     

Detection of gender-related categories by 10-month-old infants

Thirty-two 10-month-olds completed an habituation procedure where a male or female face was paired with a specific object. Results reveal 10-month-olds can form categories based on correlations among attributes of social information. Basic processes involved in gender role formation are present in 10-month-olds.     

A Gibbs sampler for the multidimensional four-parameter logistic item response model via a data augmentation scheme

The four-parameter logistic (4PL) item response model, which includes an upper asymptote for the correct response probability, has drawn increasing interest due to its suitability for many practical scenarios. This paper proposes a new Gibbs sampling algorithm for estimation of the multidimensional 4PL model based on an efficient data augmentation scheme (DAGS). With the introduction of three continuous latent variables, the full conditional distributions are tractable, allowing easy implementation of a Gibbs sampler. Simulation studies are conducted to evaluate the proposed method and several popular alternatives. An empirical data set was analysed using the 4PL model to show its improved performance over the three-parameter and two-parameter logistic models. The proposed estimation scheme is easily accessible to practitioners through the open-source IRTlogit package.