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This paper reports a before-and-after study which evaluated the impacts of installing and operating red light cameras at two "T" and one "X" signalized intersections on driver stopping propensity upon the onset of amber. Rather than using video cameras, a special purpose data logger working in conjunction with loop sensors was used to gather traffic parameters, vehicle stopping/crossing movements, and signal phases. Logistic modeling was employed to model the revealed stopping/crossing decisions of non-platoon vehicle drivers in response to the onset of amber with traffic, situational and behavioral variables, including their interactions. The results indicate that the variable Cam_Inst that gathered the impacts of red light camera (RLC) installation on driver decision-making at signalized intersection was significant at 5% level only for the camera approach model of the cross-intersection. The significance of Cam_Inst was undermined for the camera approaches at the T-intersections by the inclusion of a significant two-order variable defining the interaction of Cam_Inst with distance from the stop-line. One may, thus, infer that RLC has a fixed-quantum effect at the cross-intersection, but an accentuated effect with distance at the two T-intersections. Lastly, the effects of a RLC at an intersection on the stopping decision at the non-camera approaches were minimal.

Objective: The amount of collected field data from naturalistic driving studies is quickly increasing. The data are used for, among others, developing automated driving technologies (such as crash avoidance systems), studying driver interaction with such technologies, and gaining insights into the variety of scenarios in real-world traffic. Because data collection is time consuming and requires high investments and resources, questions like "Do we have enough data?," "How much more information can we gain when obtaining more data?," and "How far are we from obtaining completeness?" are highly relevant. In fact, deducing safety claims based on collected data-for example, through testing scenarios based on collected data-requires knowledge about the degree of completeness of the data used. We propose a method for quantifying the completeness of the so-called activities in a data set. This enables us to partly answer the aforementioned questions. Method: In this article, the (traffic) data are interpreted as a sequence of different so-called scenarios that can be grouped into a finite set of scenario classes. The building blocks of scenarios are the activities. For every activity, there exists a parameterization that encodes all information in the data of each recorded activity. For each type of activity, we estimate a probability density function (pdf) of the associated parameters. Our proposed method quantifies the degree of completeness of a data set using the estimated pdfs. Results: To illustrate the proposed method, 2 different case studies are presented. First, a case study with an artificial data set, of which the underlying pdfs are known, is carried out to illustrate that the proposed method correctly quantifies the completeness of the activities. Next, a case study with real-world data is performed to quantify the degree of completeness of the acquired data for which the true pdfs are unknown. Conclusion: The presented case studies illustrate that the proposed method is able to quantify the degree of completeness of a small set of field data and can be used to deduce whether sufficient data have been collected for the purpose of the field study. Future work will focus on applying the proposed method to larger data sets. The proposed method will be used to evaluate the level of completeness of the data collection on Singaporean roads, aimed at defining relevant test cases for the autonomous vehicle road approval procedure that is being developed in Singapore. [ABSTRACT FROM AUTHOR]

The present study aims to investigate differences in road safety attitude, driver behaviour and traffic risk perception between Malaysia and Singapore. A questionnaire-based survey was conducted among a sample of Singaporean (n= 187) and Malaysian (n= 313) road users. The data was analysed using confirmatory factor analysis and structural equation modelling applied to measure comparative fit indices of Malaysian and Singaporean respondents. The results show that the perceived traffic risk of Malaysian respondents is higher than Singaporean counterparts. Moreover, the structural equation modelling has confirmed perceived traffic risk performing the role of full mediation between perceived driving skills and perceived road safety for both the countries, while perceived traffic skills was found to perform the role of partial mediation between aggression and anxiety, on one hand, and road safety, on the other hand, in Malaysia and Singapore. In addition, in both countries, a weak correlation between perceived driving skills, aggression and anxiety with perceived road safety was found, while a strong correlation exists with traffic risk perception. The findings of this study have been discussed in terms of theoretical, practical and conceptual implications for both scholars and policy-makers to better understand the young drivers’ attitude and behaviour relationship towards road safety measures with a view to future research. [ABSTRACT FROM PUBLISHER]

Singapore has an age-based mandatory retirement policy for taxi drivers. In 2006, the upper age limit of mandatory retirement was raised from 70 to 73 years for healthy, older taxi drivers. Retirement from taxi driving in Singapore often results in simultaneous retirement from work and forced driving cessation due to limited private vehicle ownership. While both retirement from work and driving cessation have been found to have negative implications for health and wellbeing in Western countries, little is known about the effects of mandatory retirement and driving cessation for healthy professional drivers in an Asian context. This study aimed to explore the mandatory retirement experience of older Singaporean taxi drivers, aged 70–73 years. In-depth interviews were conducted within a descriptive phenomenological approach with 23 older Singaporean taxi drivers who were retired or retiring drivers. Findings showed the experience to be dominated by retirement from work issues rather than by driving cessation. Three themes described the experiences: ‘stories of taxi driving’, ‘feeling lost in retirement’ and ‘contradictions of growing old in Singapore’. Taxi driving was a valued role. Despite an expected retirement, most participants were not prepared for the retirement transition. They struggled with emotional adjustment, financial vulnerability, identity, reduction in life-space and meaningful activity participation. Participants felt under-valued despite having personal achievements and support from family and ‘successful ageing’ policies. Work remained a preferred activity despite limited re-employment opportunities. The unique context of expected but forced retirement, financial need in a non-welfare system, high cultural value on work, and limited options for productive or meaningful activities and roles, predisposed this sub-group of older Singaporean men to be vulnerable retirees in terms of identity and wellbeing issues. Support for a stressful late-life transition is indicated for continued health and wellbeing. [ABSTRACT FROM PUBLISHER]

Introduction: Older taxi drivers in Singapore face mandatory retirement at 73 years of age, often marked by the simultaneous loss of the worker and driver roles. The Driver Retirement Program was developed as an intervention to support this transition. Method: A pre- and post-experimental design was conducted with retired 73-year-old, male taxi drivers (n = 15) to investigate the hypotheses: (i) the Driver Retirement Program would increase activity participation (e.g. time use) and wellbeing (e.g. mood) outcomes at immediate post-intervention and (ii) maintain these changes at 3 months' follow-up. Non-parametric tests were used to compare changes between (i) pre- and post-intervention and (ii) 3 months follow-up to post-intervention. Participants' feedback on the Driver Retirement Program was obtained using a semi-structured questionnaire. Results: The Driver Retirement Program significantly improved mood, self-efficacy and satisfaction with individualised goals at post-intervention and maintained these changes at 3 months' follow-up. A significant decrease in time spent alone was found at follow-up compared with post-intervention. Participants rated high satisfaction with the Driver Retirement Program but also recommended a shorter programme without compulsory group sessions. Conclusion: The Driver Retirement Program was useful to support some aspects of work and driver retirement transition. Further work to enhance sensitivity to cultural and gender issues is indicated. [ABSTRACT FROM AUTHOR]

Aims: Licensing authorities in different countries differ in their approaches to the use of age based licensing, medical fitness and driving assessments. This article describes a new licensing policy introduced in Singapore in 2006 whereby driving assessment by occupational therapists became a critical stage in the licensing process for older taxi drivers. Preliminary data on the older taxi drivers are presented. Implications for future studies and clinical intervention are discussed. Methods: Information was gained from the Land Transport Authority of Singapore on current taxi drivers, the projected number of taxi drivers aged 70 years who were eligible to renew their licences in 2008, 2009, 2010, and any data on accidents, demerit points and complaints against taxi drivers. Information about the 70 year old taxi drivers that had undergone the functional driving assessment program in 2006 and 2007 was gained from the Department of Occupational Therapy. This information was analysed. Findings: There was a very high pass rate - 98% of those aged 70 or over who took the test, passed. Conclusions: The high pass rate needs further exploration. Future research can explore the cost effectiveness of the licensing and driving assessment systems in terms of accident rates, the validity of on road tests and useful predictive off road tests. [ABSTRACT FROM AUTHOR]

Driver performance in responding to the green-amber-red signal change was studied based on a sample of 2316 last crossing and first stopping vehicles collected by unobtrusive observations at 10 junction approaches in Singapore. Two schemes, a speed-distance diagram (S-D) and an acceleration-deceleration (A-D) diagram, were used to demarcate the driving situations; the driver actions, as revealed outcomes of driver decision-making, were mapped onto these diagrams. The speed-distance diagram can give some indication on what a driver would possibly do. The more complicated acceleration-deceleration diagram is useful for diagnosing the appropriateness of the driver actions. An application of the A-D diagram was demonstrated, and several situations prone to red-running were noted. [ABSTRACT FROM AUTHOR]