Reliability of variable message signs information: A field experiment study in Chongqing

A variable message sign (VMS), which is a key component of intelligent transportation systems, has been frequently used in the management of urban roads and motorways to provide drivers with real-time traffic condition information about a road section or area. Nevertheless, there is a lack of unified regulations for VMS design, which makes it difficult to accurately determine the understandability and legibility of VMS information. In practice, inappropriate designs of VMSs are common, such as overload of VMS information and excessive number of phases, particularly on the urban roads of China. Building on our earlier findings obtained by surveys, in this study, field tests were conducted to assess the reliability of VMS information in terms of the visual perception characteristics of drivers. For a full visual perception, the information displayed on a VMS must be reliable, i.e., it should be easy for drivers to detect, obtain, and understand the messages they require. Two basic theories—information theory and visual perception theory—were introduced to build a quantification model of VMS information, select evaluation indices, and design the experimental process. A total of 24 drivers participated in the field experiments and questionnaires. Five indices—information obtainment rate, periodic validity, driver subjective scoring and the corresponding UI (represents information intelligibility), and CE (represents information legibility)—were analyzed to evaluate their relationships to VMS information reliability. The results confirmed that the amount of information, and the scrolling period considering redundant distance, significantly affect the reliability of VMSs information. For static VMSs, the information obtainment rate and the subjective scoring decrease with increasing amount of information. The recollection accuracy of the drivers significantly declines when the amount of information shown increases to 90 bits, corresponding to an information obtainment rate of less than 0.8 and UI equal to 0. For dynamic VMSs, the information reliability deteriorates as the scrolling period shortens and the number of phases increases. Unreasonable reliability is found when the periodic validity is less than 0.9, i.e., the actual scrolling period is more than 10% less than the calculated one, corresponding to CE equal to 0. The reliability of information was evaluated by combining the subjective scoring of the drivers and a data-based statistical analysis and considering driving safety. Accordingly, it was recommended that 90 bit is the maximum amount of information to be shown on a VMS and that the preferred scrolling period of each phase of a dynamic VMS is 5 s. The results of this study support the objective of providing reliable information to drivers by addressing the problems related to the amount of information and presentation time for VMSs. These findings provide a basis for determining the thresholds for VMS information to promote practical and user-friendly designs of VMSs on urban roads.     

Examining generalization of motorist yielding at an adjacent crosswalk with variations of the gateway sign configuration

The gateway sign configuration has been effective at increasing motorist yielding and reducing speeds at crosswalks. A gateway configuration uses in-street signs at a crosswalk on each edge of the roadway and on each lane line. Although this intervention is effective at increasing motorist yielding at uncontrolled crosswalks, the limits of the intervention have yet to be tested. The present study examined if 1) the effects of the gateway intervention on one crosswalk would generalize to an untreated adjacent crosswalk, and 2) if the effects of an offset configuration of signs which partially treated each crosswalk could maximize the effects of that generalization. Experiment 1 showed that less yielding occurred at the untreated crosswalk than at the treated crosswalk, though yielding was higher than baseline. In Experiment 2, results showed that an offset gateway configuration could produce comparable levels of yielding at both crosswalks.     

Effects of stop signal modality, stop signal intensity and tracking method on inhibitory performance as determined by use of the stop signal paradigm

In Experiment 1, the effects of stop signal modality on the speed and efficiency of the inhibition process were examined. Stop signal reaction time (SSRT) and inhibition function slope in an auditory stop signal condition were compared to SSRT and inhibition function slope in a visual stop signal condition. It was found that auditory stop signals compared to visual stop signals enhanced both the speed and efficiency of stopping. The modality effects were attributed to differences in the neurophysiological processes underlying perception. However, Experiment 2 demonstrated that the modality difference was larger for 80 dB(A) auditory stop signals than 60 dB(A) auditory stop signals. This effect was reconciled with the suggestion that loud tones are more capable of eliciting immediate arousing effects on motor processes than weak tones and visual stimuli. The second purpose of the present investigation was to explore the utility (and potential advantages) of an alternative way of setting stop signal delay relative to mean reaction time (MRT). The method that was suggested compensates for inter-individual differences in primary task reaction speed by setting stop signal delays as proportions of the subjects' MRT.     

The ADHD Response-Inhibition Deficit as Measured by the Stop Task: Replication with DSM–IV Combined Type, Extension, and Qualification

Although response inhibition has been proposed as a core element of child attention-deficit hyperactivity disorder (ADHD), the literature is heavily reliant on studies using DSM–III–R diagnostic criteria, older methods of measuring response inhibition, samples of boys, and failing to control thoroughly for comorbid problems—both as diagnoses and as subclinical variation. The present study replicated a deficit in response inhibition in the ADHD combined type (DSM–IV, American Psychiatric Association, 1994) using samples matched on age and sex. The study replicated an effect size of approximately d = .6 in boys with ADHD, and observed an even larger effect size for girls, although the Sex × Group interaction was nonsignificant. Children with ADHD also had problems with response output, shown by variable responding. Excluding comorbid conduct disorder, reading disorder, generalized anxiety disorder, obsessive–compulsive disorder, major depression, and posttraumatic stress disorder from the sample did not alter the results. Correlations indicated that response inhibition was associated with both attentional problems and reading level. Covarying for reading problems did not eliminate the ADHD group effect, but the association of response inhibition with reading clearly requires further examination. Overall, the study supported the role of response inhibition in the DSM–IV ADHD combined type, but with key qualifications as to degree of specificity in reference both to comorbid problems and other executive functions.     

The Influence of Self-Esteem on Cognitive Responses to Machine-Like versus Human-Like Computer Feedback

Abstract

Business school students (N = 49) who were preclassified as being either high or low in self-esteem (Texas Social Behavior Inventory) interacted with a computer that delivered either human-like, neutral, or machine-like feedback. In line with a compensatory, self-enhancement perspective (Baumeister, 1982), this experiment found that persons high in self-esteem generated more negative cognitive responses and made fewer errors when faced with human-like rather than machinelike feedback from a computer. Overall, however, persons low in self-esteem did not perform more poorly than did persons high in self-esteem.     

Signs in their times: introducing a review symposium on Robert Yelle's Semiotics of Religion

This essay introduces a review symposium on Robert Yelle's Semiotics of Religion: Signs of the Sacred in History (2013). It first reviews the book's argument, then offers a selective review of the six contributions to the symposium, along with aspects of Yelle's responses to these.     

不同趋近动机强度积极情绪对认知控制的影响

情绪的动机维度模型认为, 积极情绪对认知加工的影响受其趋近动机强度的调节, 高、低趋近动机积极情绪对认知加工的影响不同。本研究运用情绪图片诱发被试高、低趋近动机积极情绪, 采用停止信号任务和任务转换作业考察了不同趋近动机强度积极情绪对认知控制的影响。结果发现：(1)与中性条件相比, 高趋近动机积极情绪促进了停止信号任务中Go任务和任务转换作业中重复任务的反应执行。(2)在停止信号任务中, 相对于中性条件, 低趋近动机积极情绪条件下的停止信号反应时显著缩短; 在任务转换作业中, 低趋近动机积极情绪条件下的反应时转换损失和错误率转换损失均显著降低, 而高趋近动机积极情绪条件下的反应时转换损失显著增加。因此, 积极情绪对认知控制的影响受其趋近动机强度的调节, 即低趋近动机积极情绪增强认知灵活性, 提高停止反应与任务转换的速度; 而高趋近动机积极情绪增强认知稳定性, 加快停止信号任务中Go任务和任务转换作业中重复任务的反应执行, 增加了反应时转换损失。     

A psychophysiological study on the function of the response‐stop in the Eriksen task1,2

Abstract: In the Eriksen task, we examined the hypothesis ( Iwaki, 1998 ) that a negative event‐related potential, which was enlarged at the frontal site synchronized with the presentation of an erroneous response causing stimulus, is related to the response‐stop function. Fourteen subjects responded selectively with their hands to the stimuli that consisted of a central target letter and surrounding compatible noise letters (e.g., HHHHH) or incompatible noise (e.g., SHHHS for small‐conflict condition or SSHSS for large‐conflict). The results showed that the increased negativity for the incompatible stimuli was synchronized with the stimulus onset but not with the response. Based on the hypothesis above, it is predicted that greater enhancement of an erroneous response by a stimulus causes the response‐stop to work harder in order to avoid an error, and this results in the larger negativity. This was supported by the evidence showing that the negativity was largest for the large‐conflict incompatible stimulus, followed by the small‐conflict, and then the compatible. We also discuss the possibility that the negativity is the NO‐GO potential concerned with the response‐stop function.     

Medical semiotics in the 18th century: A theory of practice?

Medical semiotics in the 18th century was more than a premodern form of diagnosis. Its structure allowed for the combination of empirically proven rules of instruction with the theoretical knowledge of the new sciences, employing the relation between the sign and the signified.