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1.
One of the fundamental properties of spatial vision is the ability to localize objects in space. According to a recent proposal, accurate localization performance involves the operation of two systems: the attention system and the eye movement system. Upon stimulus presentation, attention is shifted to the target area: this provides coarse location information. Subsequently, a saccadic eye movement is executed: this provides fine location information. In this study we tested predictions derived from this model concerning the effects of precue information on localization performance. In a series of five experiments we manipulated duration of precue (71, 400, and 1,000 ms) and type of precue (spatial versus symbolic). Results showed that very short duration (i.e., 71 ms) spatial precues improved localization performance whereas very short duration symbolic precues did not. In contrast, the 1,000 ms duration precue condition showed similar amounts of precuing benefit for the spatial and symbolic precues. This pattern of differential precuing effects corroborated the two-process model of localization performance. Received: 24 June 1999 / Accepted: 28 January 2000  相似文献   

2.
How do kindergarteners solve different single-digit addition problem formats? We administered problems that differed solely on the basis of two dimensions: response type (approximate or exact), and stimulus type (nonsymbolic, i.e., dots, or symbolic, i.e., Arabic numbers). We examined how performance differs across these dimensions, and which cognitive mechanism (mental model, transcoding, or phonological storage) underlies performance in each problem format with respect to working memory (WM) resources and mental number line representations. As expected, nonsymbolic problem formats were easier than symbolic ones. The visuospatial sketchpad was the primary predictor of nonsymbolic addition. Symbolic problem formats were harder because they either required the storage and manipulation of quantitative symbols phonologically or taxed more WM resources than their nonsymbolic counterparts. In symbolic addition, WM and mental number line results showed that when an approximate response was needed, children transcoded the information to the nonsymbolic code. When an exact response was needed, however, they phonologically stored numerical information in the symbolic code. Lastly, we found that more accurate symbolic mental number line representations were related to better performance in exact addition problem formats, not the approximate ones. This study extends our understanding of the cognitive processes underlying children's simple addition skills.  相似文献   

3.
The Symbolic Racism 2000 Scale   总被引:6,自引:1,他引:5  
The concept of symbolic racism was originally proposed 30 years ago. Much research has been done and the society itself has changed, yet many of the original items measuring symbolic racism remain in use. The primary objective of this paper is to present and evaluate an updated scale of symbolic racism. The scale proves to be reliable and internally coherent. It has discriminant validity, being distinctively different from both older forms of racial attitudes and political conservatism, although with a base in both. It has predictive validity, explaining whites' racial policy preferences considerably better than do traditional racial attitudes or political predispositions. Evidence is presented of its usefulness for both college student and general adult population samples, as well as for minority populations. Data using this scale contradict several critiques of the symbolic racism construct (most of which are speculative rather than based on new data) concerning the consistency of its conceptualization and measurement, the coherence of the symbolic racism belief system, possible artifacts in its influence over whites' racial policy preferences (due to content overlap between the measures of independent and dependent variables), and its differentiation from nonracial conservatism and old-fashioned racism.  相似文献   

4.
认知诊断评估旨在探讨个体内部的知识掌握结构,并提供关于学生优缺点的详细诊断信息,以促进个体的全面发展。当前研究者已开发了大量0-1评分的认知诊断模型,但对于多级评分认知诊断模型的研究还比较少。本文对已有的多级评分认知诊断模型进行了归纳,介绍了模型的假设,计量特征以及适用范围,为实际应用者和研究者在多级评分认知诊断模型的比较和选用上提供借鉴和参考。最后,对未来关于多级评分诊断模型的研究方向进行了展望。  相似文献   

5.
Finite sample inference procedures are considered for analyzing the observed scores on a multiple choice test with several items, where, for example, the items are dissimilar, or the item responses are correlated. A discrete p-parameter exponential family model leads to a generalized linear model framework and, in a special case, a convenient regression of true score upon observed score. Techniques based upon the likelihood function, Akaike's information criteria (AIC), an approximate Bayesian marginalization procedure based on conditional maximization (BCM), and simulations for exact posterior densities (importance sampling) are used to facilitate finite sample investigations of the average true score, individual true scores, and various probabilities of interest. A simulation study suggests that, when the examinees come from two different populations, the exponential family can adequately generalize Duncan's beta-binomial model. Extensions to regression models, the classical test theory model, and empirical Bayes estimation problems are mentioned. The Duncan, Keats, and Matsumura data sets are used to illustrate potential advantages and flexibility of the exponential family model, and the BCM technique.The authors wish to thank Ella Mae Matsumura for her data set and helpful comments, Frank Baker for his advice on item response theory, Hirotugu Akaike and Taskin Atilgan, for helpful discussions regarding AIC, Graham Wood for his advice concerning the class of all binomial mixture models, Yiu Ming Chiu for providing useful references and information on tetrachoric models, and the Editor and two referees for suggesting several references and alternative approaches.  相似文献   

6.
Hypotheses ranging from subsymbolic to symbolic have been proposed to account for rat sequential behaviour, and in the subsymbolic domain alone there are multiple proposed subsymbolic processes or factors thought to affect serial behaviour. A behavioural study and computer simulations were conducted to evaluate these hypotheses, and a new computational associative model based on pairwise associations and generalization was evaluated. Seven 3-element sequences were selected for study that systematically (1) varied sequence discriminability, (2) varied reward magnitude, and (3) manipulated the order of food quantities. Neither element discriminability nor response enhancement subsymbolic processes in isolation were able to account for the behavioural data; however, simulations from the computational model known as the sequential pairwise associative memory (SPAM) model with a log-linear mapping of stimulus dimension items to food quantities correlated well with the behavioural data. SPAM accounts for differential element anticipation in different sequences by appealing to pairwise association of sequence events and generalization between cues as the principal factors mediating pattern tracking in three-element sequences.  相似文献   

7.
8.
Three studies investigate how physiological emotional responses can be combined with symbolic information to predict preferences. The first study used a weighted proportional difference rule to combine explicitly quantified symbolic and emotional information. The proportion of emotion model was more predictive than a simple additive emotional (AE) combination in decisions about selecting dating partners. Study 2 showed that a simple proportion algorithm of emotionally derived weights and a simple AE model predicted preference equally well for decisions between equal expected value (EV) gambles. Study 3 provided additional evidence for decision mechanisms that combine physiological measures within symbolic trade‐off algorithms for choices between diamond rings. Self‐reported emotion measures proved to be better predictors than physiological measures. The results are discussed in the context of other major models of emotional influence on preference and provide a foundation for future research on emotional decision‐making mechanisms. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

9.
Eight experiments investigated the effects of visual, spatial, auditory, and executive interference on the symbolic comparison of animal size and ferocity, semantic goodness of words, and numbers. Dynamic visual noise (DVN) and the reading of visually presented stimulus items were shown to selectively interfere with response times on the animal size comparison task, though the slope of the symbolic distance function remained unchanged. Increased change of DVN significantly increased interference, but interference was reduced by equiluminant DVN. Spatial tracking reduced the slope of the symbolic distance function in contrast to an executive task that only increased mean latency and errors for all comparisons. Results suggest that the generation of an image is necessary for size comparison, but neither imagery nor executive function is responsible for the frequently observed distance-time function.  相似文献   

10.
Symbols can exert an influence on how we think, feel, and even behave. Here we examine whether symbolic markings serve as primes and influence how people make judgments. We propose that making either a check or an X mark to indicate an opinion can lead people to process the same information differently, thereby influencing the judgment people make. Across four experiments, we find that the check and X marks carry different symbolic associations; people associate check with good and X with bad. We also find downstream consequences of these mental associations. People who make positively connoted check marks (as opposed to negatively connoted X marks) to indicate their judgments are more agreeable toward familiar, controversial social policies as well as market research survey items on values and life styles. Differential symbolic markings with check and X marks seem to shape how people think and make judgments.  相似文献   

11.
The authors report on the development and calibration of item banks for depression, anxiety, and anger as part of the Patient-Reported Outcomes Measurement Information System (PROMIS?). Comprehensive literature searches yielded an initial bank of 1,404 items from 305 instruments. After qualitative item analysis (including focus groups and cognitive interviewing), 168 items (56 for each construct) were written in a first person, past tense format with a 7-day time frame and five response options reflecting frequency. The calibration sample included nearly 15,000 respondents. Final banks of 28, 29, and 29 items were calibrated for depression, anxiety, and anger, respectively, using item response theory. Test information curves showed that the PROMIS item banks provided more information than conventional measures in a range of severity from approximately -1 to +3 standard deviations (with higher scores indicating greater distress). Short forms consisting of seven to eight items provided information comparable to legacy measures containing more items.  相似文献   

12.
One adult female chimpanzee (Pan troglodytes) was trained to respond serially to three arabic numerals between 1 and 9, presented on a cathode-ray-tube (CRT) screen. To examine the factors affecting her sequential responding behavior, wild-card items were added to the three-item sequences. When this wild-card item remained until the subject responded to the last numeral (i.e., the terminator condition), her response to the terminator at each point of the sequence was controlled by the ordinal distance between numerals. Thus, the number of responses to the terminator increased as the ordinal distance between numerals increased. When the wild-card item was eliminated by the subject’s response (wild-card conditions), the probability of responses to the wild card before the first numeral increased as a function of the serial position of the first numeral. These results were consistent with previous studies of response time and suggest both serial position and symbolic distance effects. It is suggested that the subject might form the integrated 9-item linear representations by training of possible subsets of three-item sequences. Knowledge concerning the ordinal position of each numeral was established through this training. Received: 27 October 1999 / Accepted: 22 November 1999  相似文献   

13.
Three experiments are reported involving the presentation of lists of either letters or digits for immediate serial recall. The main variable was the presence or absence of a suffix-prefix, an item (tick or cross) occurring at the end of the list which had to be copied before recall of the stimulus list. With auditory stimuli and an auditory suffix-prefix there was a large and selective increase in the number of errors on the last few serial positions—the typical “suffix effect”. The suffix effect was not found with auditory stimuli and a visual suffix-prefix nor with a visual stimulus and an auditory suffix-prefix. These results are interpreted as supporting a model for short-term memory proposed by Crowder and Morton (1969) in which it is suggested that with serial recall information concerning the final items following auditory presentation has a different, precategorical, origin from that concerning other items.  相似文献   

14.
The present study investigated whether visual working memory (VWM) functions as a few (about 3?~ 4) fixed slots by examining how the distribution of VWM is adjusted. Adopting a change-detection paradigm, we required subjects to memorize four items, one of which was prioritized. If VWM functions as 3?~?4 slots, allocating multiple slots to the prioritized item would leave no slot for some other items; consequently no information would be stored for them, leading to a substantial decrease in change-detection performance no matter whether small or large changes occurred. The result showed that small changes on the unfavoured items were detected less accurately, indicating that more VWM was allocated to the favoured item. Yet meanwhile large changes that occurred on those unfavoured items could still be detected as well as those on the favoured one, indicating that each of them was still stored to some extent rather than completely discarded. The results suggested that VWM may not work as 3?~?4 fixed slots. Possible mechanisms were discussed based on the present results, including a modified slot model with more available slots, a continuous resource model, and a hierarchical model that assumes storage of ensemble information in addition to the information of individual items.  相似文献   

15.
Models of comparative judgment have assumed that relative magnitude is computed from knowledge about absolute magnitude rather than retrieved directly. In Experiment 1, participants verified the relative size of part-whole pairs (e.g., tree-leaf) and unrelated controls (e.g., tree-penny). The symbolic distance effect was much smaller for part-whole pairs than for unrelated controls. In two subsequent experiments, participants determined either which of two objects was closer in size to a third object or which of two pairs had a greater difference in the size of its constituents. In contrast to the paired comparison task in Experiment 1, judgments of part-whole items were more sensitive to the influence of symbolic distance than were unrelated controls. The fact that the part-whole relation attenuates the effects of symbolic distance in a paired comparison task but not in tasks that require an explicit comparison of size differences suggests that the part-whole relation provides a source of information about relative magnitude that does not depend on knowledge about absolute magnitude.  相似文献   

16.
This study aimed to establish whether the logic of the AFM applies when multielement stimuli contain relevant and irrelevant elements. Target Size (TS) and symbolic S-R Compatibility (SRC) were manipulated in three reaction time (RT) experiments. TS and SRC are assumed in the AFM literature to selectively influence the independent stages of feature extraction and S-R translation, respectively. Experiment 1 showed that the effects of TS and SRC on RT were additive when the target was presented in isolation and this additive relation was not changed when the target was flanked by stimuli that contained no information relevant to the response. In Experiment 2, this additivity changed into a superadditive interaction when flankers signaled the same response as the target: The effect of SRC was larger when targets were small rather than large. The overall pattern of findings violated the AFM stage robustness criterion. Neither a discrete stage model nor a continuous flow conception account for the results. To explain flanker effects on target processing a dual-process architecture was formulated that assumes that perceptual information is processed along concurrently engaged routes: An attentive processing route and a direct priming route. Experiment 3 confirmed the prediction of the dual-process model that the relation between TS and SRC would be subadditive when flankers signal the response opposite to that designated by the target.  相似文献   

17.
Screening preschool-aged children for disruptive behavior disorders is a key step in early intervention. The study goal was to identify screening items with excellent measurement properties at sub-clinical to clinical levels of disruptive behavior problems within the developmental context of preschool-aged children. Parents/caregivers of preschool-aged children (N?=?900) were recruited from four pediatric primary care settings. Participants (mean age?=?31, SD?=?8) were predominantly female (87 %), either white (55 %) or African-American (42 %), and biological parents (88 %) of the target children. In this cross-sectional survey, participants completed a sociodemographic questionnaire and two parent-report behavioral rating scales: the PSC-17 and the BPI. Item response theory analyses provided item parameter estimates and information functions for 18 externalizing subscale items, revealing their quality of measurement along the continuum of disruptive behaviors in preschool-aged children. Of 18 investigated items, 5 items measured only low levels of disruptive behaviors among preschool-aged children. The remaining 13 items measured sub-clinical to clinical levels of disruptive behavior problems (i.e., >1.5 SD); however, 5 of these items offered less information, suggesting unreliable measurement. The remaining 8 items had high discrimination and difficulty parameters, offering considerable measurement information at sub-clinical to clinical levels of disruptive behavior problems. Behaviors measured by the 8 selected parent-report items were consistent with those identified in recent efforts to distinguish developmentally typical misbehaviors from clinically concerning behaviors among preschool-aged children. These items may have clinical utility in screening young children for disruptive behavior disorders.  相似文献   

18.
There is a consensus that visual working memory (WM) resources are sharply limited, but debate persists regarding the simple question of whether there is a limit to the total number of items that can be stored concurrently. Zhang and Luck (2008) advanced this debate with an analytic procedure that provided strong evidence for random guessing responses, but their findings can also be described by models that deny guessing while asserting a high prevalence of low precision memories. Here, we used a whole report memory procedure in which subjects reported all items in each trial and indicated whether they were guessing with each response. Critically, this procedure allowed us to measure memory performance for all items in each trial. When subjects were asked to remember 6 items, the response error distributions for about 3 out of the 6 items were best fit by a parameter-free guessing model (i.e. a uniform distribution). In addition, subjects’ self-reports of guessing precisely tracked the guessing rate estimated with a mixture model. Control experiments determined that guessing behavior was not due to output interference, and that there was still a high prevalence of guessing when subjects were instructed not to guess. Our novel approach yielded evidence that guesses, not low-precision representations, best explain limitations in working memory. These guesses also corroborate a capacity-limited working memory system – we found evidence that subjects are able to report non-zero information for only 3–4 items. Thus, WM capacity is constrained by an item limit that precludes the storage of more than 3–4 individuated feature values.  相似文献   

19.
Thirty-four items concerning marijuana use were administered three times to a cohort of Canadian high school students between Grades 11 and 13, in 1977 (n = 439), 1978 (n = 419), and 1979 (n = 167). These items were designed to measure four distinct constructs: attitude, perceived peer approval or disapproval, concern about risks, and symbolic protest against conventional society. A cross-sectional factor analysis of the Grade 13 data supported the hypothesized factor structure, as had earlier work with college students. However, analogous analyses on the Grade 11 and Grade 12 data contradicted the hypothesized factor structure. Most notably, separate factors for positive and negative attitude appeared in the Grade 11 and 12 analyses. The data were interpreted primarily in terms of maturational changes, largely through elimination of alternative interpretations by internal analyses and previous findings. Implications were discussed for adolescent cognitive-attitudinal development, attitude theory, and analysis of panel data.  相似文献   

20.
Summary The paper argues for a distinction between sensory-and conceptual-information storage in the human information-processing system. Conceptual information is characterized as meaningful and symbolic, while sensory information may exist in modality-bound form. Furthermore, it is assumed that sensory information does not contribute to conscious remembering and can be used only in data-driven process reptitions, which can be accompanied by a kind of vague or intuitive feeling. Accordingly, pure top-down and willingly controlled processing, such as free recall, should not have any access to sensory data. Empirical results from different research areas and from two experiments conducted by the authors are presented in this article to support these theoretical distinctions. The experiments were designed to separate a sensory-motor and a conceptual component in memory for two-digit numbers and two-letter items, when parts of the numbers or items were imaged or drawn on a tablet. The results of free recall and recognition are discussed in a theoretical framework which distinguishes sensory and conceptual information in memory.  相似文献   

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