Toward a unified theory of decision criterion learning in perceptual categorization

Optimal decision criterion placement maximizes expected reward and requires sensitivity to the category base rates (prior probabilities) and payoffs (costs and benefits of incorrect and correct responding). When base rates are unequal, human decision criterion is nearly optimal, but when payoffs are unequal, suboptimal decision criterion placement is observed, even when the optimal decision criterion is identical in both cases. A series of studies are reviewed that examine the generality of this finding, and a unified theory of decision criterion learning is described (Maddox & Dodd, 2001). The theory assumes that two critical mechanisms operate in decision criterion learning. One mechanism involves competition between reward and accuracy maximization: The observer attempts to maximize reward, as instructed, but also places some importance on accuracy maximization. The second mechanism involves a flat-maxima hypothesis that assumes that the observer's estimate of the reward-maximizing decision criterion is determined from the steepness of the objective reward function that relates expected reward to decision criterion placement. Experiments used to develop and test the theory require each observer to complete a large number of trials and to participate in all conditions of the experiment. This provides maximal control over the reinforcement history of the observer and allows a focus on individual behavioral profiles. The theory is applied to decision criterion learning problems that examine category discriminability, payoff matrix multiplication and addition effects, the optimal classifier's independence assumption, and different types of trial-by-trial feedback. In every case the theory provides a good account of the data, and, most important, provides useful insights into the psychological processes involved in decision criterion learning.     

放弃治疗的伦理选择

放弃治疗在临床上是一个十分复杂的现象 ,只有将其放在“医学———文化”框架中进行全方位考察 ,才能从整体上加以正确把握。就伦理选择而言 ,放弃治疗必然面对诸多伦理冲突 ,临床医师若要化解伦理冲突 ,实现优化选择 ,就必须熟知和遵循基本的伦理准则。     

Factor analysis and AIC

The information criterion AIC was introduced to extend the method of maximum likelihood to the multimodel situation. It was obtained by relating the successful experience of the order determination of an autoregressive model to the determination of the number of factors in the maximum likelihood factor analysis. The use of the AIC criterion in the factor analysis is particularly interesting when it is viewed as the choice of a Bayesian model. This observation shows that the area of application of AIC can be much wider than the conventional i.i.d. type models on which the original derivation of the criterion was based. The observation of the Bayesian structure of the factor analysis model leads us to the handling of the problem of improper solution by introducing a natural prior distribution of factor loadings.The author would like to express his thanks to Jim Ramsay, Yoshio Takane, Donald Ramirez and Hamparsum Bozdogan for helpful comments on the original version of the paper. Thanks are also due to Emiko Arahata for her help in computing.     

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.     

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.     

概率分布等值法及其应用

在项目反应理论框架下,根据已有文献提出了开发新的测验等值准则的方法,即许多准则都可以看成是通过对锚题上作答反应概率分布进行变换而导出。据此揭示了两个著名的等值准则——Haebara方法和Stocking-Lord方法之间的联系,并且导出了一个新的等值准则——余弦等值准则。为了讨论余弦准则的行为表现,开展了一系列Monte-Carlo模拟研究。模拟结果表明,余弦准则在多级评分模型GPCM上表现比Haebara方法和Stocking--Lord方法都好,而对GRM和2PLM,其表现不如Haebara,但可以和Stocking-Lord方法相提并论。这一发现提醒我们等值准则的选用是否恰当,不仅与等值系数所落的范围有关,而且还与项目反应函数（IRF）有更密切的关系     

中西方关于心理健康标准问题的探讨及对我们的启示

分析了国内外学者在制定心理健康标准时所作的探讨,提出了适应与发展应是心理健康考察的基本对象,对心理健康的评估应是对心理机能的评估,我国在制定心理健康标准时应借鉴西方的有关理论和经验。