矩阵取样设计中的似真值能力估计方法

矩阵取样是大规模教育评估中最有效的一种数据收集方式。本研究采用模拟数据考察在均衡的不完全分块（BIB）矩阵取样设计中,似真值（PV）与传统的极大似然估计（MLE）、加权极大似然估计（WLE）和贝叶斯后验期望估计（EAP）方法对学生能力总体参数估计的精确性和稳健性。结果表明,PV对总体平均数和标准差的估计最为精确和稳健;EAP倾向于低估,MLE和WLE倾向于高估,且精确性和稳健性远远不如PV。同时,总被试量对估计结果的影响很小,而每个题本中的项目数量对估计结果的影响较大。     

基于名人面孔视觉特征和语义信息的视觉统计学习

视觉统计学习是指个体依据视觉刺激之间的转接概率来掌握统计规律的过程。本研究通过5个实验探讨了个体基于名人面孔视觉特征和语义信息进行视觉统计学习的加工机制。每个实验均包括熟悉(学习)和测试两个阶段：在熟悉阶段, 让被试观看名人面孔并完成重复图片探测的无关任务; 在测试阶段, 让被试进行二选一迫选任务。其中, 实验1和2分别考察基于名人面孔视觉特征和语义信息的视觉统计学习效果; 实验3分别考察基于名人面孔视觉特征和语义信息视觉进行统计学习的精确性; 实验4进一步考察基于名人面孔视觉特征和语义信息进行视觉统计学习的时间特征; 实验5验证基于名人面孔视觉特征的视觉统计学习具有面孔特异性。结果表明：个体能同时基于名人面孔视觉特征和语义信息进行精确的视觉统计学习; 基于正立名人面孔的视觉统计学习效果显著高于基于倒置名人面孔的视觉统计学习效果; 虽然基于视觉特征和语义信息的统计加工都具有一致的精确性, 但后者需要更多的加工时间。这提示：基于名人面孔视觉特征的视觉统计学习具有面孔特异性, 个体基于名人面孔视觉特征和语义信息的视觉统计学习过程是分离的, 统计运算发生于面孔特征加工完成之后。     

目标大小变化对多目标视觉追踪的影响

采用多目标追踪任务（MOT）对追踪过程中被试（16名）的眼动进行记录,探讨目标特征变化对视觉追踪的影响。结果表明：视觉追踪机制能够对物体的特征属性进行编码加工,但加工程度受制于目标物与分心物之间的特征竞争关系;追踪过程中,视觉系统采用知觉组织加工策略,以被追踪目标构成的多边形中心为注意中心;物体大小特征没有引起较多的外源性注意,在物体大小特征的变化条件下,视觉追踪主要是内源性的注意控制加工过程。     

动态视觉加工与儿童汉字阅读

使用视觉阈限测验、图片命名、字形相似性判断实验和语音意识等测验 ,考察了小学五年级儿童视觉加工技能与汉字阅读之间的关系。结果发现 :动态视觉加工与图片命名错误率、字形判断反应时和错误率、语音意识均有显著相关 ,静态视觉加工只与图片命名错误率相关显著 ;控制识字量后的偏相关分析显示 ,动态视觉加工与其他变量的相关关系不变 ,静态视觉加工与图片命名错误率的相关不再显著 ;回归分析发现动态视觉加工在识字量和语音意识的影响控制后 ,能够分别解释阅读流畅性、字形判断反应时和图片命名错误率 7%、2 5 %和 5 6 %的变化 ;语音意识能够解释识字量和阅读流畅性 9%和 10 %的变化 ;对差读者的动态视觉加工和语音意识分析发现 ,儿童在这两种测验上的个体差异很大。上述结果表明 ,阅读过程受基本知觉技能影响 ,动态视觉加工作用于汉字阅读的特定过程。     

道路交通标志中对称结构效应的眼动研究

本研究考察了道路交通标志中路名信息对称结构效应的眼动模式。实验采用眼动跟踪技术和视觉搜索范式,共有16名被试参加。实验结果表明：（1）在对称结构路名信息的视觉搜索中,被试的反应正确率明显优于非对称结构条件下的正确率;（2）对称结构条件下,被试的注视点和回扫次数明显较少,凝视时间明显较短;（3）在以道路交通标志为视觉搜索材料时,搜索区有无路名目标对视觉搜索绩效没有影响。可以认为：在道路交通标志中存在对称结构效应;眼动模式的差异是引起对称结构效应的认知机制。     

时间结构和速度线索对碰撞时间估计的影响

估计被遮挡的运动物体何时到达某一特定位置称为碰撞时间估计。本研究利用遮挡范式,通过控制时间结构、物理速度及运动过程是否可见设计两个（2物理速度×3时间结构）实验来探究三者对碰撞时间估计的影响。结果：当时间结构一致时,不论物理速度快慢及是否存在视觉速度线索,被试的绩效都没有显著差异;当时间结构不一致时,不论物理速度快慢,存在视觉速度条件下被试的绝对偏差小于无视觉速度条件。结论：时间结构一致时,被试主要使用时间线索进行碰撞时间估计;时间结构不一致时,被试通过整合时间结构和视觉速度线索进行估计。     

听觉经验缺失对时距估计影响的实验研究

采用复制法,通过聋人与听力正常人时距估计的对比实验研究,结果发现听觉经验缺失对时距估计有一定的影响：（1）两类被试在2000ms和10000ms的时距估计中,再现时距的平均数表现出了显著性差异。听力正常被试倾向于低估时距,聋人被试倾向于高估时距。（2）聋人被试不同时距再现相对误差率之间不存在显著性差异;听力正常被试时距再现相对错误率在2000ms与10000ms、30000ms存在显著差异,10000ms和30000ms之间差异不显著。     

“知道感”任务中的图片和字词的感受性和判断标准

该实验考察了在“知道感”（FOK）任务中的字词和图片的感受性和判断标准的差异。实验运用Hart的“回忆—FOK判断—再认”（RJR）范式,用字词和图片作为刺激材料,采用两种不同的加工水平,并根据信号检测论中的评价法对结果进行分析,结果表明：在知道感任务中,只有在线索回忆正确百分率和FOK判断等级上表现出了图片优势效应,而再认正确率和FOK准确性则没有图片优势;而且,不论是深加工还是浅加工,被试对字词和图片的感受性都没有显著性差异,但判断标准的变化较为复杂,且受加工水平的影响较大,显示出图片优势效应的产生与被试的反应偏向有关。     

攻击性信息对脆弱型高自尊大学生返回抑制的影响机制

为考察攻击性信息对脆弱型高自尊大学生返回抑制的影响机制,本研究采用线索靶子范式,分别将攻击性及中性词汇作为靶子（实验1）和线索（实验2）呈现。实验1发现,脆弱型和安全型高自尊组对攻击性信息均存在注意捕获,从而使攻击性信息的返回抑制量降低。实验2发现,脆弱型高自尊组对攻击性信息存在注意解除困难,从而使攻击性信息的返回抑制量降低。脆弱型高自尊大学生对攻击性信息存在过多的注意维持,降低了视觉搜索效率,这可是其好发攻击性行为的潜在认知加工机制。     

样例学习条件下的因果力估计

在逐个呈现因果样例的条件下,考察单一因果关系因果力估计的特点,同时检验联想解释,概率对比模型,权重DP模型,效力PC理论和pCI规则。实验让65名大学生被试估计不同化学药物影响动物基因变异的能力。实验结果表明：（1）对产生原因的因果力估计符合权重DP模型;（2）对预防原因的因果力估计较多符合效力PC理论;（3）因果力估计具有复杂多样性,难以用统一的模式加以描述和概括。     

Capacity limit of ensemble perception of multiple spatially intermixed sets

The visual system is remarkably efficient at extracting summary statistics from the environment. Yet at any given time, the environment consists of many groups of objects distributed over space. Thus, the challenge for the visual system is to summarize over multiple groups. The current study investigates the capacity and computational efficiency of ensemble perception, in the context of perceiving mean sizes of multiple spatially intermixed groups of circles. In a series of experiments, participants viewed an array of one to eight sets of circles. Each set contained four circles in the same colors, but with different sizes. Participants estimated the mean size of a probed set. The set that would be probed was either known before onset of the array (pre-cue condition) or afterwards (post-cue condition). By comparing estimation error in the pre-cue and post-cue conditions, we found that participants could reliably estimate mean sizes for approximately two sets (Experiment 1). Importantly, this capacity was robust against attention bias toward individual objects in the sets (Experiment 2). Varying the exposure time to stimulus arrays did not increase the capacity limit, suggesting that ensemble perception could be limited by an internal resource constraint, rather than the speed of information encoding (Experiment 3). Moreover, we found that the visual system could not encode and hold more individual items than ensemble representations (Experiment 4). Taken together, these results suggest that ensemble perception provides an efficient way of information processing but with constraints.     

Computation of mean size is based on perceived size

The present study investigated whether computation of mean object size was based on perceived or physical size. The Ebbinghaus illusion was used to make the perceived size of a circle different from its physical size. Four Ebbinghaus configurations were presented either simultaneously (Experiment 1) or sequentially (Experiment 2) to each visual field, and participants were instructed to attend only to the central circles of each configuration. Participants’ judgments of mean central circle size were influenced by the Ebbinghaus illusion. In addition, the Ebbinghaus illusion influenced the coding of individual size rather than the averaging. These results suggest that perceived rather than physical size was used in computing the mean size.     

Mutual interference between statistical summary perception and statistical learning

The visual system is an efficient statistician, extracting statistical summaries over sets of objects (statistical summary perception) and statistical regularities among individual objects (statistical learning). Although these two kinds of statistical processing have been studied extensively in isolation, their relationship is not yet understood. We first examined how statistical summary perception influences statistical learning by manipulating the task that participants performed over sets of objects containing statistical regularities (Experiment 1). Participants who performed a summary task showed no statistical learning of the regularities, whereas those who performed control tasks showed robust learning. We then examined how statistical learning influences statistical summary perception by manipulating whether the sets being summarized contained regularities (Experiment 2) and whether such regularities had already been learned (Experiment 3). The accuracy of summary judgments improved when regularities were removed and when learning had occurred in advance. In sum, calculating summary statistics impeded statistical learning, and extracting statistical regularities impeded statistical summary perception. This mutual interference suggests that statistical summary perception and statistical learning are fundamentally related.     

The whole is indeed more than the sum of its parts: perceptual averaging in the absence of individual item representation

We tested Ariely's (2001) proposal that the visual system represents the overall statistical properties of sets of objects against alternative accounts of rapid averaging involving sub-sampling strategies. In four experiments, observers could rapidly extract the mean size of a set of circles presented in an RSVP sequence, but could not reliably identify individual members. Experiment 1 contrasted performance on a member identification task with performance on a mean judgment task, and showed that the tasks could be dissociated based on whether the test probe was presented before or after the sequence, suggesting that member identification and mean judgment are subserved by different mechanisms. In Experiment 2, we confirmed that when given a choice between a probe corresponding to the mean size of the set and a foil corresponding to the mean of the smallest and largest items only, the former is preferred to the latter, even when observers are explicitly instructed to average only the smallest and largest items. Experiment 3 showed that a test item corresponding to the mean size of the set could be reliably discriminated from a foil but the largest item in the set, differing by an equivalent amount, could not. In Experiment 4, observers rejected test items dissimilar to the mean size of the set in a member identification task, favoring test items that corresponded to the mean of the set over items that were actually shown. These findings suggest that mean representation is accomplished without explicitly encoding individual items.     

Better than average: alternatives to statistical summary representations for rapid judgments of average size

People can perceive the individual features of an object by focusing attention on it and binding the features together at a location. Some perceptual processing can occur without focusing attention on each object, though; people may even be able to extract summary information about the sizes of all the objects in a display, essentially computing the mean size at a glance. Evidence that people can judge the mean size of an array efficiently and accurately has been used to support the strong claim that people use a global, parallel process to extract a statistical summary of the average size of the objects in the display. Such claims are based both on the accuracy of performance and on the supposition that performance exceeds what would be possible with serial, focused attention. However, these studies typically have not examined the limits of performance with focused-attention strategies. Through experiments and simulations, we show that existing evidence for mean size perception can be explained through various focused-attention strategies, without appealing to a new mechanism of average size perception. Although our evidence does not eliminate the possibility that people do perceive the average size of all the objects in a display, it suggests that simpler mechanisms can accommodate the existing data.     

Rapid extraction of mean identity from sets of faces

Recent evidence suggests that the notion that the visual system can rapidly extract summary statistics from complex scenes extends to representing sets of faces in terms of mean emotion or gender. Here we show that observers can also extract a mean identity from a set of faces with different identities. Observers first saw a set of four faces with different identities and were subsequently asked whether or not a single test face had been present in the preceding set. They were significantly more likely to respond that the test face had been present in the set if it was the morphed mean of all four set faces than when it was an actual set member. This finding suggests that representations based on summary statistics are available for face identity.     

The representation of simple ensemble visual features outside the focus of attention

The representation of visual information inside the focus of attention is more precise than the representation of information outside the focus of attention. We found that the visual system can compensate for the cost of withdrawing attention by pooling noisy local features and computing summary statistics. The location of an individual object is a local feature, whereas the center of mass of several objects (centroid) is a summary feature representing the mean object location. Three experiments showed that withdrawing attention degraded the representation of individual positions more than the representation of the centroid. It appears that information outside the focus of attention can be represented at an abstract level that lacks local detail, but nevertheless carries a precise statistical summary of the scene. The term ensemble features refers to a broad class of statistical summary features that we propose collectively make up the representation of information outside the focus of attention.     

听觉诱发表象的眼动机制

视觉心理表象是一种基于过去经验的自上而下的加工过程,它是信息表征的一种形式.以往的研究主要采用视觉来诱发表象,但是这很难排除视觉后像的干扰,而且与表象“自上而下”的加工过程不一致.听觉诱发表象很好地解决了视觉后像的干扰问题,也更吻合表象“自上而下”的加工过程,因为被试产生的表象是基于自己过去的经验,从自身出发,主动加工的结果.采用实验法,考察通过听觉通道诱发表象眼动的情况,使用眼动仪记录被试的眼动轨迹.结果发现：（1）不管是运动还是静止的物体,都能诱发表象,在表象时存在眼动行为.（2）运动的物体诱发眼动的程度更大.（3）眼动影响表象的建构,在表象建构中起机能性作用.     

Attention modulates set representation by statistical properties

Recent reports have claimed that observers show accurate knowledge of the mean size of a group of similar objects, a finding that has been interpreted to suggest that sets of multiple objects are represented in terms of their statistical properties, such as mean size (Ariely, 2001; Chong & Treisman, 2003, 2005a, 2005b). In the present study, we directed visual attention to a single set member and found that mean estimations were modulated according to the size of the attended item, regardless of whether size was the relevant search criterion (Experiment 1) or not (Experiment 2). These findings suggest that observers do not always accurately average together the entire set, and that instead the average is either biased by the features of the attended item, or based on a short-cut strategy of extracting the mean of a smaller subset.     

Hierarchical encoding in visual working memory: ensemble statistics bias memory for individual items

Influential models of visual working memory treat each item to be stored as an independent unit and assume that there are no interactions between items. However, real-world displays have structure that provides higher-order constraints on the items to be remembered. Even in the case of a display of simple colored circles, observers can compute statistics, such as mean circle size, to obtain an overall summary of the display. We examined the influence of such an ensemble statistic on visual working memory. We report evidence that the remembered size of each individual item in a display is biased toward the mean size of the set of items in the same color and the mean size of all items in the display. This suggests that visual working memory is constructive, encoding displays at multiple levels of abstraction and integrating across these levels, rather than maintaining a veridical representation of each item independently.