Effective CCTV and the challenge of constructing legitimate suspicion using remote visual images

This paper compares the effectiveness of public CCTV systems according to meta‐reviews, with what might be expected based upon theoretical predictions. The apparent gulf between practice and prediction is explored in the light of the challenges faced by CCTV operators in terms of effective target selection. In addition, counter‐intuitive reactions by members of the public to situational symbols of crime deterrence may also undermine the efficacy of CCTV. Evidence is introduced and reviewed that suggests CCTV operators may employ implicit profiles to select targets. Essentially, young, scruffy males who appear to be loitering are disproportionately targeted compared with their base rate use of surveyed areas. However, the extent to which such a profile is diagnostic of criminal intent or behaviour is unclear. Such profiles may represent little more than ‘pattern matching’ within an impoverished visual medium. Finally, suggestions for future research and effective CCTV operator practice are offered in order to improve target selection. Copyright © 2008 John Wiley & Sons, Ltd.     

文字与图片呈现形成想象空间记忆的比较

学习通过文字或图片方式显示的空间布局材料之后,采用空间定位任务．分别检验在不同朝向和相对位置的条件下,对想象空间方位判断的差异。结果表明,使用图片进行空间布局的学习,记忆后再各自以同样显示形式进行空间定位任务时,判断的速度比使用文字的反应时要快;同时,无论是文字还是图片形式呈现．在进行想象转向时．都会呈现朝向效应和相对位置效应。     

FOK判断与可接近信息之间的关系

通过三个实验,用语义联想集大小不同的中文单字词研究了靶项目联想集的大小与FOK判断等级和准确性的关系。实验一通过两种不同联想集大小的靶子,比较外显的、提取出的信息和内隐的、语义网络中固有的被激活信息量对FOK判断等级和FOK判断准确性是否有不同的影响。实验二和实验三通过不同的靶子呈现时间和学习遍数,比较不同的识记强度对不同大小联想集的靶子的FOK判断等级和FOK判断准确性的影响。实验结果表明：FOK判断等级随外显的、提取出的信息总量的增多而增高,随内隐的、语义网络中固有的被激活信息量的增多而降低。FOK判断准确性随靶子本身的激活强度的增强而增高,随内隐的、语义网络中固有的被激活信息的激活强度的增强而降低,FOK判断准确性取决于这两种激活强度的综合作用。     

视空工作记忆负载对真实场景搜索绩效的影响

采用视空工作记忆任务和真实场景搜索任务相结合的双任务范式, 结合眼动技术将搜索过程划分为起始阶段、扫描阶段和确认阶段, 探究视空工作记忆负载对真实场景搜索绩效的影响机制, 同时考查试次间搜索目标是否变化、目标模板的具体化程度以及搜索场景画面的视觉混乱度所起的调节作用。结果表明, 视空工作记忆负载会降低真实场景搜索的成绩, 在搜索过程中表现为视空负载条件下扫描阶段持续时间的延长、注视点数目的增加和空间负载条件下确认阶段持续时间的延长, 视空负载对搜索过程的影响与目标模板的具体化程度有关; 空间负载会降低真实场景搜索的效率, 且与搜索画面的视觉混乱度有关, 而客体负载则不会。由此可见, 视空工作记忆负载对真实场景搜索绩效的影响不同, 空间负载对搜索过程的影响比客体负载更长久, 二者均受到目标模板具体化程度的调节; 仅空间负载会降低真实场景的搜索效率, 且受到搜索场景画面视觉混乱度的调节。     

场景情境和目标模板在视觉搜索中的交互作用

以真实场景图像中的物体搜索为实验任务, 操纵场景情境和目标模板, 采用眼动技术将搜索过程分为起始阶段、扫描阶段和确认阶段, 考察场景情境和目标模板对视觉搜索过程的影响机制。结果发现, 场景情境和目标模板的作用方式及时间点不同, 二者交互影响搜索的正确率和反应时, 仅场景情境影响起始阶段的时间, 随后二者交互影响扫描阶段和确认阶段的时间及主要眼动指标。作者由此提出了场景情境和目标模板在视觉搜索中的交互作用模型。     

选择集大小对网购决策态度和行为的影响

研究探讨网络购物中选择集大小对决策态度和行为的影响,以及目标确定性和产品类型对该关系的调节作用。采用2(大选择集vs.小选择集)×2(目标明确vs.目标不明确)×2(体验型产品vs.搜索型产品)的组间设计,发现大选择集组选择满意度、自信心更高,但延迟选择更多,出现态度-行为分离。目标不明确时,大选择集组延迟选择更多。     

靶子的潜在位置数对辨别任务中返回抑制的影响

摘要在严格控制的条件下,以大学生为被试．采用线索一靶子模式的返回抑制范式．考察了靶子在注视点周边可能出现的位置数与辨别任务中返回抑制的关系。实验结果表明．在辨别任务中靶子的潜在位置数对返回抑制量有影响,随着位置数的增加,返回抑制量减小。该结论为返回抑制的注意性观点提供了新的证据。     

Working memory capacity predicts search accuracy for novel as well as repeated targets

Visual search behaviour is guided by mental representations of targets that direct attention toward relevant features in the environment. Electrophysiological data suggests these target templates are maintained by visual working memory during search for novel targets and rapidly transfer to long term memory with target repetition. If this account is correct, an individual’s working memory capacity should be more predictive of search performance for novel targets than repeated targets. Across six experiments, we tested this hypothesis using both single (Experiments 5 and 6) and multiple (Experiments 1–4) target search tasks with three different types of stimuli (real world objects, letters, and triple conjunction shapes). Each target set was repeated for six consecutive trials. In addition, we estimated visual working memory capacity using a change detection working memory task. Overall, working memory capacity did not predict response time or efficiency in the visual search task. However, working memory capacity was equally predictive of search accuracy for both novel and repeated targets. These results suggest that working memory requirements do not substantially differ between novel and repeated target search, and working memory capacity may continue to play an important role in the encoding or maintenance of target representations after they are presumed to be in long term memory.     

Target selection patterns in rape

Both theoretical and empirical studies of decision making in target selection have shown that this process is highly dependent on the physical environment. However, research specifically investigating decision making in sex offenders' target selection is scarce. The aims of the current study were to (1) identify target selection patterns in a mixed sample of 78 Canadian and Portuguese adult rapists, (2) investigate how geographical decision making influences target selection patterns, and (3) test the influence of the type of environment on target selection patterns. The results indicate that Canadian and Portuguese rapists exhibit different target selection patterns but that their geographical decision making is congruent and consistent with the environment within which they operate. Copyright © 2010 John Wiley & Sons, Ltd.     

不同难度刺激材料的汉字特性负启动效应研究

负启动的研究是考察选择性注意中抑制机制的基本实验范式。本研究选取不同难度的刺激材料,使用经典的负启动实验范式,分别从增加目标选择难度和干扰项个数两个方面考察了大学生被试的汉字特性负启动效应。结果发现：在目标和干扰项互为形似字以及多个干扰项的情况下,被试的特性负启动效应均消失。此结果为注意的资源分配理论提供了进一步的证据。