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Safety-in-numbers: A systematic review and meta-analysis of evidence
Get PDFThis paper presents a systematic review and meta-analysis of studies that have estimated the relationship between the number of accidents involving motor vehicles and cyclists or pedestrians and the volume of motor vehicles, cyclists and pedestrians. A key objective of most of these studies has been to determine if there is a safety-in-numbers effect. There is safety-in-numbers if the number of accidents increases less than proportionally to traffic volume (for motor vehicles, pedestrians and cyclists). All studies reviewed in the paper are multivariate accident prediction models, estimating regression coefficients that show how the number of accidents depends on the conflicting flows (pedestrians, cyclists, motor vehicles), as well as (in some of the models) other factors that influence the number of accidents. Meta-analysis of regression coefficients involves methodological problems, which require careful consideration of whether the coefficients are sufficiently comparable to be formally synthesised by means of standard techniques of meta-analysis. The comparability of regression coefficients was assessed. It was concluded that a formal synthesis of regression coefficients in studies of the safety-in-numbers effect is defensible. According to a random-effects inverse-variance meta-analysis, the summary estimates of the regression coefficients for traffic volume are 0.50 for motor vehicle volume, 0.43 for cycle volume and 0.51 for pedestrian volume. Estimates are highly consistent between studies. It is concluded that a safety-in-numbers effect exists. It is still not clear whether this effect is causal, nor, if causal, which mechanisms generate the effect.submittedVersio
Speed enforcement in Norway: Testing a game-theoretic model of the interaction between drivers and the police
Get PDFThis paper probes the relationship between changes in the risk of apprehension for speeding in Norway and changes in the amount of speeding. The paper is based on a game-theoretic model of how the rate of violations and the amount of enforcement is determined by the interaction between drivers and the police. This model makes predictions both about how drivers will adapt to changes in the amount of enforcement (the more enforcement, the less violations) as well as how the police will adapt to changes in the rate of violations (the less violations, the less enforcement). The paper attempts to test the game-theoretic model empirically. Testing the model rigorously is difficult, mainly because some of the relevant variables are not reliably measured and are endogenous. Two models were developed: one to identify sources of changes in the rate of violations, one to identify sources of changes in the amount of enforcement. The predictions of the game-theoretic model were supported, although the results were not statistically significant in the model of how the police adapt enforcement to changes in the rate of violations.acceptedVersio
A theoretical perspective on road safety communication campaigns
Get PDFThis paper proposes a theoretical perspective on road safety communication campaigns, which may help in identifying the conditions under which such campaigns can be effective. The paper proposes that, from a theoretical point of view, it is reasonable to assume that road user behaviour is, by and large, subjectively rational. This means that road users are assumed to behave the way they think is best. If this assumption is accepted, the best theoretical prediction is that road safety campaigns consisting of persuasive messages only will have no effect on road user behaviour and accordingly no effect on accidents. This theoretical prediction is not supported by meta-analyses of studies that have evaluated the effects of road safety communication campaigns. These analyses conclude that, on the average, such campaigns are associated with an accident reduction. The paper discusses whether this finding can be explained theoretically. The discussion relies on the distinction made by many modern theorists between bounded and perfect rationality. Road user behaviour is characterised by bounded rationality. Hence, if road users can gain insight into the bounds of their rationality, so that they see advantages to themselves of changing behaviour, they are likely to do so. It is, however, largely unknown whether such a mechanism explains why some road safety communication campaigns have been found to be more effective than others.submittedVersio
Competitive tendering in an entry regulated market—an accident waiting to happen?
Get PDFIntroduction Competitive tendering was introduced in the contract segment of the Norwegian taxi industry in 2005; a market characterised by entry regulation. Using this reform as a natural experiment this research looks into how competitive tendering has resulted in different outcomes in different segments of the taxi market and which explanations are best at describing the results. Methods The main sources of data are the taximeter data and case studies, conducted as part of a study of the rural taxi industry in Norway. This data have been supplemented by interviews with key stakeholders and data on prices and volumes from various purchasers of transport services, such as health corporations and county governments. Results The empirical data shows a lot of variation. There are very different outcomes in the different cases studied. However, the research shows that competitive tendering has mostly worked according to intention in the most central regions. These are characterised by many potential suppliers and that the tendered contracts are relative small compared with the total size of the market. I rural areas the results differ, with poor results from tendering in the intermediate areas and mostly satisfactory results in the most rural areas. Conclusions Experience from the Norwegian taxi industry shows that competitive tendering is possible within entry-regulated markets. Still, there are issues that remain to be solved, in particular in rural areas. This is due to both interdependency between the purchaser and the service provider, and the size of the markets. For other sectors, the main lessons are that competitive tendering can work, even with regulated entry, but that it needs to be adapted to suit the characteristics of each market. This research shows that there is significant variation within a sector. A tool such as competitive tendering can be well suited in one area, but inappropriate in another. This research suggests that the outcome is related to both hard factors such as market size and number of entrants, but also to factors like interdependency and negotiation climate.publishedVersio
Safety effects of fixed speed cameras - An empirical Bayes evaluation
Get PDFThe safety effects of 223 fixed speed cameras that were installed between 2000 and 2010 in Norway were investigated in a before–after empirical Bayes study with control for regression to the mean (RTM). Effects of trend, volumes, and speed limit changes are controlled for as well. On road sections between 100 m upstream and 1 km downstream of the speed cameras a statistically significant reduction of the number of injury crashes by 22% was found. For killed and severely injured (KSI) and on longer road sections none of the results are statistically significant. However, speed cameras that were installed in 2004 or later were found to reduce injury crashes and the number of KSI on road sections from 100 m upstream to both 1 km and 3 km downstream of the speed cameras. Larger effects were found for KSI than for injury crashes and the effects decrease with increasing distance from the speed cameras. At the camera sites (100 m up- and down-stream) crash reductions are smaller and non-significant, but highly uncertain and possibly underestimated.acceptedVersio
Traffic accidents triggered by drivers at work - A survey and analysis of contributing factors
Get PDFThis report outlines the results of a study of severe road traffic accidents in Norway, triggered by drivers at work. The aim has been to examine whether and to what extent risk factors of these triggering drivers and their vehicles can be traced back to work-related factors. The study is based on data from the Accident Analysis Groups (AAG) of the Norwegian Public Roads Administration (NPRA), reports from The Transport Accident Investigation Board Norway (AIBN) and interviews with nine experts. The quantitative analysis of AAG data shows that too high speed for the circumstances, failure to use seat belt and insufficient information gathering were the most important risk factors in fatal accidents triggered by drivers at work. The qualitative analysis of reports from AIBN and expert interviews uncovered the following work-related factors considered central for traffic safety: follow up of drivers’ speed, driving style and use of seat belt, pay systems, safety culture, risk assessments, procedures/work descriptions and training. The AIBN reports and the interviews indicate that the following framework conditions influence traffic safety: time pressure, competition, type of transport, accident investigations/inspections. The majority of the interviewees held that work-related factors with potential implications for traffic safety are insufficiently monitored in controls and inspections.acceptedVersio
Asymmetric preferences for road safety: Evidence from a stated choice experiment among car drivers
Get PDFRecent research has proposed fitting responses from discrete choice experiments to asymmetric value functions consistent with prospect theory, taking into account respondents’ reference points in their valuation of choice attributes. Previous studies have mainly concentrated on travel time and cost attributes, while evidence regarding road safety attributes is very limited. This paper investigates the implicit utility of a road safety attribute, defined as the number of casualties per year in alternative car trip choices, when safety improves or deteriorates. Using appropriate statistical tests we are able to reject symmetric preferences for losses and gains in the level of safety and estimate a sigmoid value function that exhibits loss aversion and diminishing sensitivity. This adds an interesting psychological dimension to the preference of road safety. Possible implications of this finding for policy making are discussed.submittedVersio
Standards for usable and safe environments for sight impaired
Get PDFWhen revising national standards and guidelines facilitating for sight-impaired people in transport systems, Norwegian authorities needed an assessment of current standards and practices. Two issues concerning design of streetscapes and public transport stops were of particular concern for the authorities: tactile paving seems to be laid out in situations in which more thoughtful design with natural leading elements could better have ensured usability, accessibility and safety for sight impaired; and there is a lack of consistency where tactile paving is laid out, causing potentially dangerous situations. The aim of this paper is to discuss how and why qualities of standards and guidelines, as well as of current practices, contribute to planning and design processes producing such results, and furthermore to arrive at recommendations for improving the situation.acceptedVersio
Policy packages and state engagement: Comparing car-use reduction policy in two Norwegian cities
No full textAnders Tønnesen, Policy packages and state engagement: Comparing car-use reduction policy in two Norwegian cities, Journal of Transport Geography, Volume 46, 2015, Pages 89-98, ISSN 0966-6923, https://doi.org/10.1016/j.jtrangeo.2015.06.006.Policy packages are structures used to combine different policy measures and address multiple objectives. This paper links local-level policy packaging with national authorities’ environmental strategies. Applying a multilevel-governance perspective, it examines how state engagement influences the integration of car-use reduction strategies in local policy packages. Two policy packages are empirically compared, one from the larger Norwegian city of Trondheim and one from the mid-sized city of Bodø. While both policy packages reveal ambivalence in whether to facilitate or restrict car usage, the strategies employed in Trondheim to mitigate the effects of road building are stronger than those used in Bodø. In Trondheim, more resources are used for climate-friendly transport and stronger regulation is applied to integrate land-use and transport policy. In explaining this, different levels of state engagement are emphasised. The study reveals how, both financially and in the building of institutional capacity, the approach of national authorities prioritises the larger city.Policy packages and state engagement: Comparing car-use reduction policy in two Norwegian citiesacceptedVersio
Tourist Segments for New Facilities in National Park Areas: Profiling Tourists in Norway Based on Psychographics and Demographics
Get PDFThe pursuit of sustainable tourism may involve development of more facilities in the buffer zones of national parks and other pristine nature areas. Two independent samples of domestic and foreign tourists in Norway were segmented based on expressed preferences for a diversity of new facilities in an alpine national park region, all facilities potentially with different impacts on the natural habitat. One sample was recruited inside the alpine area, the other outside. Post hoc market segmentation was carried out using a combined two-stage hierarchical and nonhierarchical clustering of facility quest factors identified from a set of survey items. We assessed stability of the clusters by comparing independent sample solutions against the pooled sample and further assessing the extent to which the clusters differed with respect to demographic or psychographic characteristics.acceptedVersio