Factors affecting motorcyclists’ behavior in car-following condition

Car-following (CF) maneuver plays an important role in both traffic flow analysis and road safety assessment. However, many studies on this issue have focused on the drivers’ behaviour, neglecting the different driving behaviour of the motorcycle riders and the vulnerability of this type of user. The aim of the present paper is to analyse the factors affecting the riders’ behaviour in CF condition, by using two surrogate safety indicators, Time Headway (TH) and Time To Collision (TTC). A field experiment was conducted to collect data. Twenty young motorcyclists participated in the study driving their own motorcycles, which were instrumented with a camera and a global positioning system device (GPS). A digital image processing algorithm was used to obtain CF related indicators. The results of the study showed that Time Headway (TH) and Time To Collision (TTC) are independent of each other, extending the result obtained in the literature for the four wheeled vehicles to the motorcycles. TTC and TH were therefore analyzed separately. As for TTC, it was observed that only in few cases (0.8%) the riders were found in risky condition (TTC < 5 s), confirming the role of this parameter for the detection of an impending risk. On the other hand, TH gives information about a potentially risky situation, and 99% of the riders were found in such condition (TH < 2 s). Due to the few cases in TTC risky conditions, only TH was further modelled by using the hazard-based duration analysis. Accelerated Failure Time (AFT) model specification was used, and the Weibull distribution provided the best fit of the data. The model identified four covariates affecting TH and all of them had the effect of reducing TH, increasing the collision risk. The time spent on CF condition, the speed of the motorcycle, the willingness of overtaking and the engine size of the motorcycle were the factors that reduced TH.The findings of this study could be considered in the development of microsimulation models; the factors that were found affecting the motorcyclists’ behavior in car-following condition could be considered for a more realistic simulation of the riders’ choice of Time Headway.     

How accurate are memories of traffic accidents? Increased false memory levels among motorcyclists when confronted with accident-related word lists

Previous studies have found that false memories increase when people receive stimuli which is related to their knowledge base. In the current set of four experiments, we examined how accident experience affected false memory production among motorcyclists using different types of false memory word lists. Specifically, Experiments 1, 2, and 3 were conducted involving motorcyclists with and without accident experience, whereas Study 4 was conducted on non-motorcyclists without accident experience. In all experiments, participants were given associatively-related word lists known to foster false memory creation. Different types of word lists were used consisting of accident-related words, emotionally-negative words, and neutral words. Levels of false memory were measured using recall and recognition tests. We found consistent results in Experiments 1, 2, and 3 in which among motorcyclists, accident-related words produced higher levels of false memory than emotionally-negative and neutral words. This pattern was not observed in Experiment 4 where non-motorcyclists were involved. Our results shed light on the role of previous experience on false memory formation. One implication could be that the police should be careful with reports of motorcyclists' experiences about their accidents as motorcyclists may spontaneously come up with false, but related details concerning these experiences.     

“They have to be better than human drivers!” Motorcyclists’ and cyclists’ perceptions of autonomous vehicles

Road users and the general population by and large recognise the value of vehicles with automated driving systems and features (otherwise typically known as Autonomous Vehicles (AVs)) in terms of road safety, reduced emissions and convenience, but are still wary of their capability, preferring the ‘comfort zone’ of human operator intervention. Motorcyclists and cyclists conversely, are vulnerable to human fallibility in driving, with the majority of crashes occurring as a consequence of other drivers’ inattention. The transition period associated with the introduction of AVs will require AVs and motorcyclists/cyclists sharing the road for a number of years yet, so we need to understand motorcyclists’/cyclists’ perception of AVs. The question of interest here is whether motorcyclists/cyclists reflect the historical literature in this area by having higher levels of trust for human drivers over AVs, or whether they have higher levels of trust in AVs because it removes the ‘human element’ that has been proven to be particularly dangerous for them. Here we surveyed motorcyclists and cyclists about their trust in human drivers and AVs, and developed a novel suite of questions designed to interrogate the difference between trust in general versus trust as a concept of their own personal safety. Some of the salient outcomes suggest that motorcyclists have medium to low levels of trust for both human drivers and AVs, but are significantly more likely to believe that AVs are safer in terms of their own personal safety, such as prioritising or detecting the rider, compared to human drivers. This relationship varies with age and crash experience. The results here are consistent with the logic that motorcyclists/cyclists have a heightened sense of vulnerability on the road and welcome the introduction of AVs as a way of mitigating personal risk when riding. This insight will be crucial to the subsequent roll-out of AVs in the future.     

Randomized trial of an official contact letter intended to increase proper licensure among unlicensed motorcycle owners

BackgroundApproximately one-third of all fatality-injured motorcycle operators in California from 1999 through 2008 were not properly licensed to ride a motorcycle at the time of the crash. In availing themselves of a licensing system, motorcyclists are afforded the opportunity to acquire and demonstrate the minimum knowledge and skills necessary to operate motorcycles on public roadways, and licensing allows agencies to monitor their riding performance and apply appropriate sanctions, with the overall goal being enhanced safety. To that end, a randomized trial was conducted of an intervention recommended by the National Highway Traffic Safety Administration to increase proper motorcycle licensure.MethodsOfficial contact letters providing information about obtaining a motorcycle license, and the potential legal consequences of riding without one, were mailed to owners of currently-registered California motorcycles who were not licensed to ride motorcycles. Half of the 65,766 improperly licensed California motorcycle owners identified were randomly assigned to be mailed the contact letter while the remainder served as a no-letter control group. The groups were compared on 33-month post-treatment motorcycle licensure rates and 18-month post-treatment motorcycle crashes and traffic violations.ResultsWhile a modestly higher percentage of motorcycle owners who were mailed the contact letter became properly licensed (14.5%) than those who were not mailed the letter (10.4%), the majority (85.5%) remained improperly licensed to operate a motorcycle 33 months later. The effect of the contact letter was influenced by owner age, whereby the odds of licensure for those to whom the letter was sent increased significantly for owners aged 20–34 (21%), 35–54 (47%), and 55 and older (96%). No 18-month post-treatment differences in motorcycle crash involvements or traffic violations were found.ConclusionGiven the traffic-safety neutral outcomes and relatively low cost of treatment, official contact letters should be considered in other jurisdictions to increase proper motorcycle licensure as recommended by the National Highway Traffic Safety Administration. Future letters may be more effective if they are tailored to the demographic characteristics (e.g., age and sex) of the owners.     

Analysis of correlations between psychological factors and self-reported behavior of motorcyclists in Malaysia,depending on self-reported usage of different types of motorcycle facility

Segregated road lanes for motorcyclists are one of the practices implemented by the Malaysian authority to decrease the number of road crashes involving motorcycles. In this study, the motorcycle lanes are divided into three types, exclusive, inclusive, and paved shoulder. This study examined the correlations between motorcyclists’ psychological factors and their risky riding behaviors (speeding and neglecting to wear helmet), depending on self-reported usage of different types of motorcycle facilities. The psychological factors discussed in this study were: attitude, desire, perceived behavior control, moral obligation, perceived danger, fear of being caught, and perception of others’ behaviors toward the risky behaviors. Quantitative analyses, including Structural Equation Modeling, were used as the analytical tools. The results demonstrated the statistically significant relationship of exclusive road lanes’ usage on speeding behavior. However, no statistically significant correlation was found for segregated lanes’ usage on helmet wearing behavior. Psychological factors were found affecting the motorcyclists’ likelihood of performing the risky behaviors. However, these factors influence speeding and helmet wearing behavior differently. The study offers recommendations and theoretical contributions to explain the complex relationships among the uses of segregated lanes, riders’ psychological factors, and their risky behaviors.     

Factors associated with red-light running among motorcyclists at signalised junctions in Malaysia

Red-light running (RLR) among motorcyclists at signalised junctions (SJ) in Malaysia are common. This study investigates factors associated with RLR among motorcyclists at signalised junctions. The observation was conducted in 2016–2017, at 26 signalised junctions nationwide, and was analysed using the mixed-effect logistic regression. Out of the 53,475 observed vehicles, only 3.6% run the red light (by which 99% are motorcycles), and from the 19,232 observed motorcycles, 26.2% among motorcyclists run the red light while 54.1% of them, run the red-light without stopping. Factors associated with a high probability of RLR are male riders who do not wear a helmet, who approach the SJ via lane split, who cross SJ via turning, SJ with no traffic island, and SJ with the presence of vehicles waiting on one or both legs. The random parameters show that the majority (83%) of variation in the outcomes occurs among the riders (at Level 1), which suggest that motorcyclists’ characteristics and riding behaviour are still the main factors in affecting the RLR occurrences and require more in-depth study. While 1.5% of variation occurs among the type of motorcycle by region (at Level 2), it also shows that RLR occurs regardless. Other variations are from the range of median width (3.9% at Level 3) and the speed limit range along major roads (9.5% at Level 4). To reduce RLR among motorcyclists, we are recommending that SJ be equipped with traffic islands, and replace the overhead signal pole with pedestal pole.     

The impact of daytime running (LED) lights on motorcycles speed estimation: A driving simulator study

Motorcycles are the most common type of vehicle involved in traffic deaths, especially in underdeveloped and developing countries. In order to prevent traffic accidents involving motorcyclists, one of the measures is to respect the “see and be seen” rule. If a motorcycle is perceived in time or another motorcyclist is spotted in time, there is enough time to react, in order to avoid a traffic accident or reduce the consequences. In many countries, it is for this reason that the use of daytime running lights on motor vehicles and/or motorcycles is legally prescribed. In the Republic of Serbia, a country that belongs among the least developed countries, about a third of those killed in traffic accidents are motorcycle drivers. For these reasons, an experimental study was conducted on a driving simulator to examine the importance of (non) use of daytime running lights on the estimation of motorcycle speed. Three different situations were examined: without daytime running lights, with daytime running lights, and with LED daytime running lights; for test speeds of 30 km/h, 50 km/h, 70 km/h, and 90 km/h. In the experiment, 128 young drivers participated. The results showed that the speed of a motorcycle with LED daytime running lights on is perceived most accurately.