Local response-rate constancy on concurrent variable-interval schedules of reinforcement

Concurrent variable-interval schedules were arranged with a main key that alternated in color and schedule assignment, along with a changeover key on which a small fixed ratio was required to changeover. Acceptable matching was observed with pigeons in two replications, but there was a tendency toward overmatching. Local response rates were found to differ for unequal schedules of a concurrent pair: local response rate was greater for the variable-interval schedule with the smaller average interreinforcement interval, but qualifications based on an interresponse-time analysis were discussed. In a second experiment, two 3-minute variable-interval schedules were arranged concurrently, and the experimental variable was the changeover procedure: either a changeover delay was incurred by each changeover or a small fixed ratio on a changeover key was required to complete a changeover. Changeover delays of 2 and 5 seconds were compared with a fixed-ratio changeover of five responses. The response output on the main key (associated with the variable-interval schedules) was greater when a changeover delay was arranged than when a fixed ratio was required to changeover. A detailed analysis of stripchart records showed that a 2-second delay generated an increased response rate for 3 seconds after a changeover, while the fixed-ratio requirement generated an increased rate during the first second only, followed by a depressed response rate for 2 seconds.     

When are item response models consistent with observed data?

The problem of deciding whether a set of mental test data is consistent with any one of a large class of item response models is considered. The classical assumption of locla independence is weakened to a new condition, local nonnegative dependence (LND). Necessary and sufficient conditions are derived for a LND item response model to fit a set of data. This leads to a condition that a set of data must satisfy if it is to be representable by any item response model that assumes both local independence and monotone item characteristic curves. An example is given to show that LND is strictly weaker than local independence. Thus rejection of LND models implies rejection of all item response models that assume local independence for a given set of data.This research was supported in part by Grant NIE-G-78-0157 to ETS from the NIE, by the Program Statistics Research Project, and by TOEFL Program Research. I would like to thank Dr. Douglas Jones of ETS for stimulating discussions during the early stages of this research, Dr. Frederick Lord of ETS for his encouragement of this work and comments on earlier drafts of this paper and Professor Robert Berk of Rutgers University for pointing out that conditions (a), (b) and (c) of Theorem 2 were also sufficient for LND and Monotonicity. Dr. Donald Alderman of ETS provided financial support for the development of a computer program to apply these results to data from the TOEFL program.     

Local homogeneity in latent trait models. A characterization of the homogeneous monotone irt model

The stochastic subject formulation of latent trait models contends that, within a given subject, the event of obtaining a certain response pattern may be probabilistic. Ordinary latent trait models do not imply that these within-subject probabilities are identical to the conditional probabilities specified by the model. The latter condition is called local homogeneity. It is shown that local homgeneity is equivalent to subpopulation invariance of the model. In case of the monotone IRT model, local homogeneity implies absence of item bias, absence of item specific traits, and the possibility to join overlapping subtests. The following characterization theorem is proved: the homogeneous monotone IRT model holds for a finite or countable item pool if and only if the pool is experimentally independent and pairwise nonnegative association holds in every positive subpopulation.This research was supported by the Dutch Interuniversity Graduate School of Psychometrics and Sociometrics. The authors wish to thank two reviewers for their thorough comments.     

高创造力个体的群体差异性研究

高创造力群体的界定是创造力研究的重要前提,但迄今极少有研究关注以往研究中高创造力群体间的同质性问题。本研究以创造力问题提出能力测验调查了两所高校（一所地方高校和一所教育部直属高校）的975名大学生的创造力,通过极端组方法（extreme groups approach, EGA）为大学生创造力水平分组,考察不同创造力分组之间的差别。研究发现：地方高校和部属高校的高创造力大学生被试,在创造力的流畅性、变通性和独特性三个维度上,均存在显著差异。本研究结果提示,大学生高创造力组间可能存在质的差别,因此相关研究在外推结果时需要采取谨慎态度;研究者在实验过程中和讨论文献结果的可比性时一定要关注样本的同质性问题。     

文本信息的激活与整合：阅读优生与差生的比较

探讨阅读优生与差生文本阅读过程中文本信息的激活与整合模式,包括3个实验。实验一通过运用不一致实验范式（inconsistent paradigm）考察阅读优生与阅读差生能否形成整体连贯性与局部连贯性。结果发现,阅读差生难以形成整体连贯性。实验二运用探测－核证范式（probe-verification paradigm）通过比较在三个位置后（人物特征描述、填充段落、目标句）的探测句的反应时间,探讨阅读差生不能形成整体连贯性的原因是由于不能激活先前的信息,还是整合信息时出现了问题。结果发现阅读差生与优生一样都可以激活先前的信息,说明阅读差生不能形成整体连贯性的原因可能是整合的问题。实验三进一步验证了阅读差生不能形成整体连贯性的原因是由于不能把已经激活的信息很好地加以整合所致。     

Comparing score tests and other local dependence diagnostics for the graded response model

Score tests for identifying locally dependent item pairs have been proposed for binary item response models. In this article, both the bifactor and the threshold shift score tests are generalized to the graded response model. For the bifactor test, the generalization is straightforward; it adds one secondary dimension associated only with one pair of items. For the threshold shift test, however, multiple generalizations are possible: in particular, conditional, uniform, and linear shift tests are discussed in this article. Simulation studies show that all of the score tests have accurate Type I error rates given large enough samples, although their small‐sample behaviour is not as good as that of Pearson's Χ² and M₂ as proposed in other studies for the purpose of local dependence (LD) detection. All score tests have the highest power to detect the LD which is consistent with their parametric form, and in this case they are uniformly more powerful than Χ² and M₂; even wrongly specified score tests are more powerful than Χ² and M₂ in most conditions. An example using empirical data is provided for illustration.     

Situating Standards in Practices: Multi Drug-Resistant Tuberculosis Treatment in India

Public health care needs to cope with a basic dilemma between providing standardized care within public programmes across entire and at times resource-constrained countries and adapting this care locally when responding to individual needs. This tension between standardization and local adaptation becomes particularly obvious for the prolonged and complicated treatment of multidrug-resistant tuberculosis (MDR-TB). Situated standardization, as introduced by Zuiderent-Jerak [2007a, 2007b] offers a way out of this dilemma. It helps to focus on how standards need to be situated in practice rather than viewing standardization and local adaptation as mutually exclusive practices. How do actors relate standardization and individual care in their practices of treating MDR-TB? Results from qualitative fieldwork at the first MDR-TB treatment sites of the Indian TB programme show that actors situate standards in a particular way. They assess the role of guidelines in a particular situation and on that basis recognize the core recommendations of guidelines or go beyond the guidelines. This allows actors to negotiate how standards should be situated and reconciles the dilemma between local adaptation and standardization. Having guidelines internalized, as is common for Indian TB control, bears both promises and pitfalls for engaging in standardization processes in a situated manner. The results contribute to science and technology study scholarship on guideline development. They highlight how actors coordinate the situating of standards and how this depends upon cultures of control. This illustrates the potential of qualitative studies on local adaptation for guideline developers by revealing existing practices of relating and negotiating local adaptation and standardization.     

题组反应理论及其在中学英语考试中的应用研究

题组作为众多测验中的一种常见题型,由于项目间存在一定程度的依赖性而违背了局部独立性假设,若用项目反应模型进行参数估计将会出现较大的偏差.题组反应理论将被试与题组的交互作用纳入到模型中,解决了项目间相依性的问题.笔者对题组反应理论的发展、基本原理及其相关研究进行了综述,并将其应用在中学英语考试中.与项目反应理论相对比,结果发现：（1）题组反应模型与项目反应模型在各参数估计值的相关系数较强,尤其是能力参数和难度参数;（2）在置信区间宽度的比较上,题组反应模型在各个参数上均窄于项目反应模型,即题组反应模型的估计精度优于项目反应模型.     

Testing day: The effects of processing bias induced by Navon stimuli on the strength of the Müller-Lyer illusion

Explanations for the cognitive basis of the Müller-Lyer illusion are still frustratingly mixed. To date, Day’s (1989) theory of perceptual compromise has received little empirical attention. In this study, we examine the merit of Day’s hypothesis for the Müller-Lyer illusion by biasing participants toward global or local visual processing through exposure to Navon (1977) stimuli, which are known to alter processing level preference for a short time. Participants (N = 306) were randomly allocated to global, local, or control conditions. Those in global or local conditions were exposed to Navon stimuli for 5 min and participants were required to report on the global or local stimulus features, respectively. Subsequently, participants completed a computerized Müller-Lyer experiment where they adjusted the length of a line to match an illusory-figure. The illusion was significantly stronger for participants with a global bias, and significantly weaker for those with a local bias, compared with the control condition. These findings provide empirical support for Day’s “conflicting cues” theory of perceptual compromise in the Müller-Lyer illusion.     

Absolute and relative pitch: Global versus local processing of chords

Absolute pitch (AP) is the ability to identify or produce notes without any reference note. An ongoing debate exists regarding the benefits or disadvantages of AP in processing music. One of the main issues in this context is whether the categorical perception of pitch in AP possessors may interfere in processing tasks requiring relative pitch (RP). Previous studies, focusing mainly on melodic and interval perception, have obtained inconsistent results. The aim of the present study was to examine the effect of AP and RP separately, using isolated chords. Seventy-three musicians were categorized into four groups of high and low AP and RP, and were tested on two tasks: identifying chord types (Task 1), and identifying a single note within a chord (Task 2). A main effect of RP on Task 1 and an interaction between AP and RP in reaction times were found. On Task 2 main effects of AP and RP, and an interaction were found, with highest performance in participants with both high AP and RP. Results suggest that AP and RP should be regarded as two different abilities, and that AP may slow down reaction times for tasks requiring global processing.