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The current study explored the effect of on-road experiences with an automated shuttle (AS) on vulnerable road users' (VRUs) expectations about the AS's actions. It was also explored whether experience interacted with situational characteristics, subjects' trust in ASs and functional understanding of ASs in affecting expectations. Subjects were presented with an online questionnaire in which they had to indicate their expectations about the AS's actions in different visualized traffic situations as well as their previous experience with, trust in and functional understanding of ASs. The findings indicate that experience by itself had no influence on expected AS behavior. Yet, experience did have an effect in interaction with situational characteristics, trust and understanding, suggesting that multiple factors playa role in forming VRUs' expectations about the behavior of an AS.

Relying on accident records as the main data source for studying cyclists’ safety has many drawbacks, such as high degree of under-reporting, the lack of accident details and particularly of information about the interaction processes that led to the accident. It is also an ethical problem as one has to wait for accidents to happen in order to make a statement about cyclists’ (un-)safety. In this perspective, the use of surrogate safety measures based on actual observations in traffic is very promising. In this study we used video data from three intersections in Norway that were all independently analysed using three methods: the Swedish traffic conflict technique (Swedish TCT), the Dutch conflict technique (DOCTOR) and the probabilistic surrogate measures of safety (PSMS) technique developed in Canada. The first two methods are based on manual detection and counting of critical events in traffic (traffic conflicts), while the third considers probabilities of multiple trajectories for each interaction and delivers a density map of potential collision points per site. Due to extensive use of microscopic data, PSMS technique relies heavily on automated tracking of the road users in video. Across the three sites, the methods show similarities or are at least “compatible” with the accident records. The two conflict techniques agree quite well for the number, type and location of conflicts, but some differences with no obvious explanation are also found. PSMS reports many more safety-relevant interactions including less severe events. The location of the potential collision points is compatible with what the conflict techniques suggest, but the possibly significant share of false alarms due to inaccurate trajectories extracted from video complicates the comparison. The tested techniques still require enhancement, with respect to better adjustment to analysis of the situations involving cyclists (and vulnerable road users in general) and further validation. However, we believe this to be a future direction for the road safety analysis as the number of accidents is constantly decreasing and the quality of accident data does not seem to improve. © 2016 Elsevier Ltd. All rights reserved.

Background. Traditional crash-based analysis of road safety at individual sites has its shortcomings due to low numbers and the random nature of crashes at individual sites and the related statistical issues, as well as the under-reporting of crashes and lack of information on contributing factors and the process preceding crashes. To get around the problem, road safety analysis based on surrogate measures of safety, i.e. not based on crashes, can be used. However, the question whether surrogate measures are valid indicators for safety remains unanswered and only a few attempts have actually been made to carry out proper large-scale validation studies. Aim. This work presents a methodological approach for a large-scale validation study of surrogate safety indicators focusing on vulnerable road users. With only one site analyzed so far, it presents the exploration of the data and of the performance of the technical tools used in the study. Method. Video-filming and consequent video analysis are used to measure the surrogate safety indicators. In the first step, the video is “condensed” using a watchdog software RUBA that selects situations with an encounter of a cyclist or pedestrian and a motor vehicle. At a later stage, the trajectories of the individual road users are produced using a semi-automated tool T-Analyst and several surrogate safety indicators are tested to set a severity score for an encounter. The performance of the surrogate indicators will be compared to the expected number of accidents at each site and availability of the data for developing a safety performance function (SPF) that is country-, manoeuvreand type of VRU-specific are explored. Results & Conclusion. From methodological perspective, limited accident data available seriously complicates building a reliable SPF (“ground truth”) against which the surrogate safety measures could be validated; some other, “indirect” methods of validation might be required. We present also the performance of the software tools and applicability of the various surrogate safety indicators that were tested.

In The Netherlands, on bicycle paths, single-bicycle accidents, bicycle-bicycle and bicycle-moped accidents constitute a considerable share of all bicyclist injuries. Over three quarters of all hospitalised bicyclist victims in the Netherlands cannot be directly related to a crash with motorised traffic. As the usage of bicycle paths steadily increases, it is to be expected that safety on bicycle paths will become a major issue in the coming years in The Netherlands. A study was conducted into the behaviour of bicyclists and moped riders to improve traffic safety on bicycle paths. By behavioural observations with video, mutual conflicts and bicyclist behaviour on bicycle paths were recorded and analysed, among other things by means of the conflict observation method DOCTOR (Dutch Objective Conflict Technique for Operation and Research). The explorative phase of the study (phase 1), included two research locations, one in the city of Amsterdam and one in Eindhoven. The results gave guidance for a better understanding of the behaviour between different users of separate two-directional bicycle paths. An example includes the relationship between bicyclist-moped rider behaviour and the width of the bicycle path. For a condition with busy bicycle traffic in both directions the width of the bicycle path in Amsterdam (effectively 3.55 m) is relatively narrow, whereas the bicycle path width in Eindhoven (>4.94 m) appears to be sufficient to accommodate large flows of bicyclists. Because of a large flow of crossing pedestrians resulting in (severe) conflicts with bicyclists in Amsterdam, additional countermeasures to better control these interactions are needed. The DOCTOR conflict observation method from video appears to be applicable for conflicts between intersecting road users and for head-on conflicts on the bicycle path. Conflict situations between bicyclists in the same direction (constituting an important share of injury accidents on bicycle paths) require an additional and more general systematic observation of specific behaviour. Therefore, phase 2 of the project will focus in particular on interactions between bicycle path users in the same direction and underlying processes. © 2013 Elsevier Ltd.

Object-location memory is the only spatial task where female subjects have been shown to outperform males. This result is not consistent across all studies, and may be due to the combination of the multi-component structure of object location memory with the conditions under which different studies were done. Possible gender differences in object location memory and its component object identity memory were assessed in the present study. In order to disentangle these two components, an object location memory task (in which objects had to be relocated in daily environments), and a separate object identity recognition task were carried out. This study also focused on the conditions under which object locations were encoded and retrieved. Only half of the participants were aware of the fact that object locations had to be retrieved later on. Moreover, by applying the 'process dissociation procedure' to the object location memory assessments and the 'remember-know' paradigm to the object identity measure, the amount of explicit (conscious) and implicit (unconscious) retrieval was estimated for each component. In general, females performed better than males on the object location memory task. However, when controlled for object identity memory, females no longer outperformed males, whereas they did not obtain a higher general object identity memory score, nor did they have more explicit or implicit recollection of the object identities. These complicated effects might stem from a difference between males and females, in the way locations or associations between objects and locations are retrieved. In general, participants had more explicit (conscious) recollection than implicit (unconscious) recollection. No effect of encoding context was found, nor any interaction effect of gender, encoding and retrieval context.

Item does not contain fulltext One of the most consistent findings in the area of cognitive sex differences is that males outperform females on many spatial tasks. One exception seems to be object location memory. On this task, females tend to perform better than males. However, the existing studies have provided quite mixed results and the picture is far from clear. Important moderators not systematically controlled for thus far are encoding context, the way information is retrieved from memory and the multiple component aspect of object location memory. The aim of our research was to investigate-gender differences within and between automatic and controlled encoding (incidental-intentional) and retrieving (explicit-implicit) contexts-if and how memory for objects is related to memory for object locations. Object location memory was assessed by a task in which objects had to be relocated within (pictures of) different rooms. Different encoding contexts were created by varying instructions between subjects. The way in which subjects retrieved the object locations was assessed by means of the Processing Dissociation Procedure developed by Jacoby. A separate object recognition task was conducted in order to measure memory for the objects. In general, females performed better than males on the object location memory task. However, when controlled for object memory, females no longer outperformed males, whereas they did not obtain a higher object recognition score, nor did they have more contextual recollection of the object identities. This indicates that a female advantage probably occurs somewhere else in the process of binding objects to locations. In general, participants had more conscious recollection than unconscious recollection. No effect of encoding context was found, nor any interaction effect of gender, encoding and retrieval context. 1 p.

The chapter primarily focuses on observing traffic conflicts (also known as near-accidents) as a site-based road safety analysis technique. Traffic conflicts are a type of surrogate safety measure. The term surrogate indicates that non-accident-based indicators are used to assess VRU safety instead ofthe more traditional approach focusing on accidents (see chapter 2). The theory underpinning surrogate safety measures is briefly described, followed by a discussion on the characteristics of the traffic conflict technique. Next, guidelines for conducting traffic conflict observations using trained human observers or video cameras are presented. Chapter 4 concludes with examples of the use of the traffic conflict technique in road safety studies focusing on VRUs.