Estimating effectiveness of speed reduction measures for pedestrian crossing treatments using an empirically supported speed choice modeling framework

Pedestrian crossing treatments, such as Pedestrian Hybrid Beacons (PHBs) and Rectangular Rapid-Flashing Beacons (RRFBs), are traffic control devices implemented to help pedestrians safely cross busy or higher-speed roadways at midblock crossings and uncontrolled intersections. This study aims to assess the effectiveness of the PHB and RRFB by analyzing drivers’ speeding behavior under different roadway types with real-life traffic conditions. In order to understand the effect of pedestrian crossing treatments (i.e., PHB and RRFB) have on drivers’ speeding behavior, this paper analyzes four zones (i.e., one upstream zone and three consecutive downstream zones). For the four analysis zones, different indexes were computed which corresponds to the differences in drivers’ speed when encountered with the pedestrian crossing treatments. A grouped random effect hurdle beta regression model is estimated for the indexes, with a fixed effect hurdle beta model used for comparison and validating the importance of considering the grouped random heterogeneity across participants. The proposed analysis framework was validated by the means of an empirical driving simulator study, based on two urban roads in the Central Florida region, North Alafaya Trail (SR-434) and South Orange Blossom Trail (US-441). The results revealed that the proposed modeling framework reflects drivers’ difference in speed for the different pedestrian crossing treatments. The results suggest that with proper understanding of the PHB, the PHB can reduce drivers speed even beyond the location of the PHB. Meanwhile, the RRFB does have some effect in speed reduction beyond the location of the RRFB, however many drivers failed to acknowledge the RRFB. It is suggested that when drivers’ have proper education on the use of the PHB to reduce speed safely and for the installation of RRFB be on roads with two or less lanes and a speed limit less than 40 mph. While the main purpose of the pedestrian crossing treatments is to help pedestrians cross safely, speed reduction can be considered a byproduct as revealed in this study.     

Driving distraction at night: The impact of cell phone use on driving behaviors among young drivers

Currently, young drivers are more likely than other drivers to use cell phones while driving at night, which has become a major cause of road crashes. However, limited attention has been given to distracted nighttime driving. Therefore, the aim of this study was to explore the interaction effect of cell phone use and time of day (daytime and nighttime) on young drivers’ car-following performance. Forty-three young drivers engaged in a driving simulator experiment with a within-subject design that included three distractions (no distraction, talking and texting on a cell phone) and two times of day. This paper applied non-parametric tests to analyze the data and obtained the following results: (1) the standard deviation of lane position (SDLP) did not significantly differ at either time of day under no distraction, but it was significantly higher at night on straight roads and large-radius curves after introducing distractions. In addition, participants drove faster and gave less headway on small-radius curves under both distractions at night; (2) texting significantly increased the SDLP, while there was less lateral variation during the talking tasks than under no distraction on simple road sections; and (3) compared with the experienced drivers, the novice drivers drove faster during the talking tasks on small-radius curves, but there was no significant difference between groups during the texting tasks. These findings provide both theoretical and practical implications for related policy makers to enhance traffic safety.     

An analysis of factors affecting wrong-way driving at a highway entrance using a driving simulator among older drivers with cognitive decline

About 200 highway wrong-way driving cases occur annually in Japan, of which about 70% are caused by older drivers. The number of these cases has remained consistent despite adoption of full-fledged measures against wrong-way driving, thus demonstrating the need for further measures. Reports indicate that older drivers include those with cognitive decline. Moreover, it has been revealed that drivers over 75 years of age who caused wrong-way driving had lower test scores in the usual cognitive function tests performed at the time of licence renewal. However, there is no clear evidence on the relationship between cognitive decline and driving behaviour that stimulates wrong-way driving. In this paper, we reproduced a wrong-way driving approaching a right turn to an expressway exit in a virtual environment using a driving simulator for older drivers, including those with mild cognitive impairment (MCI). In addition to the measurement of driving behaviour and eye-tracking during simulator driving, we conducted a cognitive function test to investigate the relationship between driving behaviour and visual behaviour factors that initiate reverse running and cognitive decline. The results revealed that the reason for the start of a highway wrong-way driving may be a human error at the recognition stage of overlooking a visual wrong-way driving countermeasure, or a human error at the judgement stage of failing to suppress action despite noticing the visual countermeasure. Additionally, attentional and executive functions were related to the wrong-way initiative, although MCI did not affect it. This suggests that those who could not control their wrong-way driving behaviour despite observing the signs had specific executive function deficits.     

Young adult couples’ behavioral and physiological responses to the infant simulator: A preliminary illustration of coparenting

This exploratory application of the infant simulator with two couples is designed to illustrate individual reactivity and coparenting behaviors in young couples in serious relationships who do not yet have children. A 35-min protocol with standardized onsets and offsets of inconsolable baby cries was used to capture partner’s individual behavioral and physiological responses as well as the couple’s joint efforts to soothe the crying baby. Task feasibility was demonstrated by couples’ persistent and wide-ranging efforts to calm the baby including rocking, feeding, changing, talking to the baby, and singing. Within-person fluctuations in ongoing heart rate (HR) and electrodermal activity (EDA) through the protocol suggested evidence of heightened physiological reactivity during baby crying compared to silence. During bouts of crying, higher HR also was evidenced when participants took the lead in caregiving as contrasted with assisting or busying themselves in another task. Behavioral observations indicated that this task elicited examples of coparenting behaviors including cooperation, support, undermining, and negotiating the division of labor. These preliminary pilot data demonstrate the potential of infant simulator paradigms with couples who are not yet pregnant but envision being future parents, and set the stage for future research to identify how individual and couple characteristics might impact reactions to shared baby caregiving.     

Experimental evidence supporting simpler Action Point paradigms for car-following

The Action Point theory is one of the paradigms that can be applied to understand and reproduce car-following behaviour. Several different approaches to this theory have been proposed, some more simple and others more complex. In particular, the reference point in this field is still the paradigm from Wiedemann, which requires the identification of four action-point thresholds. In this paper we review Action Point theories in order to highlight similarities and differences and to ascertain whether all the thresholds proposed by Wiedemann actually bind the driving behaviour. Based on a large-scale experiment in which car-following data were collected, we identified all candidate action points assuming that the more complex (four-threshold) theory holds. Then we tested these points with respect to the large data set of available observations, in order to check whether actual actions are performed at the points. The results show that very often simpler approaches better match the observed data and that in order to explain car-following behaviour it is sufficient in most cases to refer to two thresholds. The results obtained by real-world observation were also tested in virtual environments (two different kinds of driving simulators) and were confirmed.     

Young driver distraction by text messaging: A comparison of the effects of reading and typing text messages in Chinese versus English

BackgroundReading and typing text messages while driving seriously impairs driving performance and are prohibited activities in many jurisdictions. Hong Kong is a bilingual society and many people write in both Chinese and English. As the input methods for text messaging in Chinese and English are considerably different, this study used a driving simulator approach to compare the effects of reading and typing Chinese and English text messages on driving performance.MethodThe driving performances of 26 participants were monitored under the following conditions: (1) no distraction, (2) reading and typing Chinese text messages, and (3) reading and typing English text messages. The following measures of driving performance were collected under all of the conditions: reaction time (RT), driving lane undulation (DLU), driving speed fluctuation (DSF), and car-following distance (CFD) between test and leading cars.ResultsRT, DLU, and DSF were significantly impaired by reading and typing both Chinese and English text messages. Moreover, typing text messages distracted drivers more than reading them. Although the Chinese text messaging input system is more complicated than the English system, the use of Chinese did not cause a significantly different degree of distraction.ConclusionBoth reading and typing text messages while driving should be prohibited regardless of whether Chinese or English is used.     

Driving on familiar roads: Automaticity and inattention blindness

This paper describes our research into the processes that govern driver attention and behavior in familiar, well-practiced situations. The experiment examined the effects of extended practice on inattention blindness and detection of changes to the driving environment in a high-fidelity driving simulator. Participants were paid to drive a simulated road regularly over 3 months of testing. A range of measures, including detection task performance and driving performance, were collected over the course of 20 sessions. Performance from a yoked Control Group who experienced the same road scenarios in a single session was also measured. The data showed changes in what drivers reported noticing indicative of inattention blindness, and declining ratings of mental demand suggesting that many participants were “driving without awareness”. Extended practice also resulted in increased sensitivity for detecting changes to road features associated with vehicle guidance and improved performance on an embedded vehicle detection task (detection of a specific vehicle type). The data provide new light on a “tandem model” of driver behavior that includes both explicit and implicit processes involved in driving performance. The findings also suggest reasons drivers are most likely to crash at locations very near their homes.     

Affective components in training to ride safely using a moped simulator

The aim of the present research was to compare different methods of training for safe moped use, especially focusing on physiological reactions during risky experiences. By recording skin conductance response (SCR), we investigated whether training that requires active riding behavior in different risky situations through the use of the Honda Riding Training (HRT) simulator leads to different physiological reactivity, which, in turn, might lead to better learning outcomes. Results indicated that participants who rode actively through the HRT showed higher percentages of SCRs than participants who simply observed risky road scenes to spot hazards. SCR percentage was higher in scenes with no accident. Overall, SCR amplitude was greater when accidents occurred than in scenes with no accidents. Implications for the effectiveness of inexperienced riders training with riding simulators were also discussed.     

Measuring being lost in thought: An exploratory driving simulator study

In driver behaviour research there is considerable focus on distraction caused by specific external systems, such as navigation systems or mobile telephones. However, it is not clear whether self-paced actions such as daydreaming have the same negative effects on driving behaviour. In a driving simulator study, the effects of an internal cognitive process (internal distraction) on driving behaviour and physiological data were compared to the effects of a sound and speech task (external distraction). Three groups of participants made two drives on a motorway, with one control group, one internal distraction group and one external distraction group. Dependent measures included driving behavioural measures, physiological measures and a subjective indication of participants’ experienced involvement in the driving task.The effects of both the internal and external distraction task were reflected in speed, number of lane changes, deceleration, glances and subjective ratings. When an effect was found for both the internal and the external distraction task, the results indicated similar (negative) effects. Participants also indicated that they had the feeling they were less involved in the driving task with both secondary tasks.