Essential independence and likelihood-based ability estimation for polytomous items

A definition ofessential independence is proposed for sequences of polytomous items. For items satisfying the reasonable assumption that the expected amount of credit awarded increases with examinee ability, we develop a theory ofessential unidimensionality which closely parallels that of Stout. Essentially unidimensional item sequences can be shown to have a unique (up to change-of-scale) dominant underlying trait, which can be consistently estimated by a monotone transformation of the sum of the item scores. In more general polytomous-response latent trait models (with or without ordered responses), anM-estimator based upon maximum likelihood may be shown to be consistent for under essentially unidimensional violations of local independence and a variety of monotonicity/identifiability conditions. A rigorous proof of this fact is given, and the standard error of the estimator is explored. These results suggest that ability estimation methods that rely on the summation form of the log likelihood under local independence should generally be robust under essential independence, but standard errors may vary greatly from what is usually expected, depending on the degree of departure from local independence. An index of departure from local independence is also proposed.This work was supported in part by Office of Naval Research Grant N00014-87-K-0277 and National Science Foundation Grant NSF-DMS-88-02556. The author is grateful to William F. Stout for many helpful comments, and to an anonymous reviewer for raising the questions addressed in section 2. A preliminary version of section 6 appeared in the author's Ph.D. thesis.     

A note on the investigation of local and global identifiability

In general, nonlinear models such as those commonly employed for the analysis of covariance structures, are not globally identifiable. Any investigation of local identifiability must either yield a mapping of identifiability onto the entire parameter space, which will rarely be feasible in any applications of interest, or confine itself to the neighbourhood of such points of special interest as the maximum likelihood point.The author would like to thank J. Jack McArdle and Colin Fraser for their comments on this paper.     

Effects of two teacher-presentation rates on off-task behavior, answering correctly, and participation

Off-task behavior, correct answering, and participation during beginning reading instruction were recorded for two low-achieving first-grade children during two different rates of teacher presentation. A slow-rate presentation (A) was compared with a fast-rate presentation (B) in an ABABAB design. In slow-rate presentation, there was a delay between the children's response and introduction of the next task. In fast-rate presentation, there was no delay. A new teacher taught during the final AB phases, which allowed for a brief replication. Both teachers were reminded on a fixed-interval 90-sec schedule throughout all phases of the experiment to praise the subjects, thus preventing a confounding of social praise and rate of teacher presentation. Fast-rate presentation was accompanied by a lower per cent occurrence of off-task behavior for both Subjects 1 and 2. For Subject 1, correct answering and participation were more frequent during all three fast-rate phases. For Subject 2, correct answering and participation were more frequent during the fast-rate phases after the first reversal.     

语音信息对不同水平中国英语学习者语义加工的影响

研究通过同音异义词对被试判断句子语义正误的干扰实验,来考查语音信息对不同英语水平的中国英语学习者语义加工的影响。实验结果发现,英语水平较高的中国被试所受到的同音异义词的干扰较大,而英语水平普通的被试受到的干扰很小。这一结果说明,英语学习者的水平越高,其语音信息的使用程度越高。     

Gradedness of visual awareness depends on attentional scope: Global perception is more graded than local perception

The gradedness or discreteness of our visual awareness has been debated. Here, we investigate the influence of spatial scope of attention on the gradedness of visual awareness. We manipulated scope of attention using hierarchical letter-based tasks (global: broad scope; local: narrow scope). Participants reported the identity of a masked hierarchical letter either at the global level or at the local level. We measured subjective awareness using the perceptual awareness scale ratings and objective performance. The results indicate more graded visual awareness (lesser slope for the awareness rating curve) at the global level compared to the local level. Graded perception was also observed in visibility ratings usage with global level task showing higher usage of the middle PAS ratings. Our results are in line with the prediction of level of processing hypothesis and show that global/local attentional scope and contextual endogenous factors influence the graded nature of our visual awareness.     

阴谋论信念的产生机制——社会认知视角的三种解释

社会心理学将阴谋论视作一种意识形态上的信念,并定义为人们将重大的政治或社会事件归因为有权力的群体或个人暗中预谋以达成其目的的解释倾向。社会认知视角为个体这种阴谋论信念的产生提供了三种解释。错觉模式感知导致人们认知上倾向于在不相关的事件之间建立联系;敏感性动因觉察影响人们过度感知并假定事件背后的动因、目的和意图等;投射是将自己愿意参与阴谋的意图归因于事件中的他人。     

Aggression-consistent, -inconsistent,and -irrelevant priming effects on selective exposure to media violence

Priming with aggressive concepts increases males' attraction to media violence. It was hypothesized that priming with schema-irrelevant concepts would decrease interest relative to the effects of schema-relevant concepts, whether or not the schema-relevant concepts were also schema-consistent. Thirty male undergraduates used lists including aggressive (schema-consistent and schema-relevant), positive or prosocial (schema-inconsistent yet relevant), or entirely neutral (schema-irrelevant) words to write short stories (priming task), then received an opportunity to select videotaped film clips for viewing. Subjects primed by aggressive word lists included more aggression, anger, fear, and violence in their stories than did those in the aggression-inconsistent and aggression-irrelevant conditions, whereas aggression-inconsistent priming yielded more fun, helping, and joy than did other conditions. Aggressively primed subjects expressed more interest in films containing violence and hostility than did neutrally primed subjects, whereas aggression-inconsistent priming did not differ significantly from either aggressive (schema-consistent) or neutral (schema-irrelevant) priming. Findings indicate that the aggressive priming activates aggressive concepts that make violence and hostility more salient to individuals. Because male undergraduates typically express interest in violence, enhanced salience leads to increased interest. © 1992 Wiley-Liss, Inc.     

Pictures and repeated exposure increase perceived accuracy of news headlines

Fake news, deliberately inaccurate and often biased information that is presented as accurate reporting, is perceived as a serious threat. Recent research on fake news has documented a high general susceptibility to the phenomenon and has focused on investigating potential explanatory factors. The present study examined how features of news headlines affected their perceived accuracy. Across four experiments (total N = 659), we examined the effects of pictures, perceptual clarity, and repeated exposure on the perceived accuracy of news headlines. In all experiments, participants received a set of true and false news headlines and rated their accuracy. The presence of pictures and repeated exposure increased perceived accuracy, whereas manipulations of perceptual clarity did not show the predicted effects. The effects of pictures and repeated exposure were similar for true and false headlines. These results demonstrate that accompanying pictures and repeated exposure can affect evaluations of truth of news headlines.