analysis of pedestrian accident costs in Sudan using the willingness-to-pay method

The willingness-to-pay (WTP) with contingent valuation (CV) method has been proven to be a valid tool for the valuation of non-market goods or socio-economic costs of road traffic accidents among communities in developed and developing countries. Research on accident costing tends to estimate the value of statistical life (VOSL) for all road users by providing a principle for the evaluation of road safety interventions in cost-benefit analysis. As in many other developing countries, the economic loss of traffic accidents in Sudan is noticeable; however, analytical research to estimate the magnitude and impact of that loss is lacking. Reports have shown that pedestrians account for more than 40% of the total number of fatalities. In this study, the WTP-CV approach was used to determine the amount of money that pedestrians in Sudan are willing to pay to reduce the risk of their own death. The impact of the socioeconomic factors, risk levels, and walking behaviors of pedestrians on their WTP for fatality risk reduction was also evaluated. Data were collected from two cities—Khartoum and Nyala—using a survey questionnaire that included 1400 respondents. The WTP-CV Payment Card Questionnaire was designed to ensure that Sudan pedestrians can easily determine the amount of money that would be required to reduce the fatality risk from a pedestrian-related accident. The analysis results show that the estimated VOSL for Sudanese pedestrians ranges from US$0.019 to US$0.101 million. In addition, the willingness-to-pay by Sudanese pedestrians to reduce their fatality risk tends to increase with age, household income, educational level, safety perception, and average time spent on social activities with family and community.     

The value of statistical life in road safety: a meta-analysis

Costs of accidents make up an important part of the total external cost of traffic. A substantial proportion of accident costs is related to fatal accidents. In the evaluation of fatal accident costs the availability of an estimate of the economic value of a statistical life is pivotal. We present an overview of the empirical literature on the value of statistical life in road safety (VOSL), and use meta-analysis to determine variables that explain the variation in VOSL estimates reported in the literature. We show that the magnitude of VOSL estimates depends on the value assessment approach (particularly, stated versus revealed preference), and for contingent valuation studies also on the type of payment vehicle and elicitation format. We explain that VOSL estimates cannot simply be averaged over studies. The magnitude of VOSL is intrinsically linked to the initial level of the risk of being caught up in a fatal traffic accident and to the risk decline implied by the research set-up.     

Value of statistical life: adults versus children

Most studies on the value of statistical life (VOSL) and values for prevention of injuries provide only the average values for the overall population. It is often argued that the values for children may be higher than that for adults because parents are usually more concerned about the mortality and morbidity risks of their children than for themselves. However, it is not an easy task to determine separate VOSLs for children and adults. Only a few empirical results are available and they do not show a definite pattern. Using the results of a value of safety survey carried out in New Zealand in 1997–1998, this paper investigates whether the willingness to pay based VOSL is higher or lower for children. Formal statistical tests were carried out to test the differences and also a regression analysis was carried out to estimate the VOSL separately for adults and children, particularly in households with children. The analysis shows that for the whole sample, the value is higher for children. However, when some outliers were removed the results indicate a higher value for adults than for children. A further trimming shows the value of children is slightly higher. Therefore, no definite conclusion could be drawn. Households without children have the highest VOSL.     

Willingness-to-pay for reducing fatal accident risk in urban areas: an Internet-based Web page stated preference survey

Contemporary transport project evaluation requires the ability to value reductions in the number of estimated fatal and non-fatal accidents after project implementation. In this quest, we designed a stated preference (SP) experiment to estimate willingness-to-pay (WTP) for reducing fatal accident risk in urban areas. The survey was implemented in a Web page allowing rapid turnover and a complete customisation of the interview. The sample was presented with a series of route choice situations based on travel time, cost and number of car fatal accidents per year. With this data we estimated Multinomial Logit (MNL) and Mixed Logit (ML) models based on a consistent microeconomic framework; the former with linear and non-linear utility specifications and allowing for various stratifications of the data. The more flexible ML models also allow to treat the repeated observations problem common to SP data and, as expected, gave a better fit to the data in all cases. Based on these models, we estimated subjective values of time, that were consistent with previous values obtained in the country, and also sensible values for the WTP for reductions in fatal accident risk. Thus, the Internet appears as a potentially very interesting medium to carry out complex stated choice surveys.     

Value of a statistical life in road safety: A benefit-transfer function with risk-analysis guidance based on developing country data

We model a value of statistical life (VSL) transfer function for application to road-safety engineering in developing countries through an income-disaggregated meta-analysis of scope-sensitive stated preference VSL data. The income-disaggregated meta-analysis treats developing country and high-income country data separately. Previous transfer functions are based on aggregated datasets that are composed largely of data from high-income countries. Recent evidence, particularly with respect to the income elasticity of VSL, suggests that the aggregate approach is deficient because it does not account for a possible change in income elasticity across income levels. Our dataset (a minor update of the OECD database published in 2012) includes 123 scope-sensitive VSL estimates from developing countries and 185 scope-sensitive estimates from high-income countries. The transfer function for developing countries gives VSL = 1.3732E−4 × (GDP per capita)^∧2.478, with VSL and GDP per capita expressed in 2005 international dollars (an international dollar being a notional currency with the same purchasing power as the U.S. dollar). The function can be applied for low- and middle-income countries with GDPs per capita above $1268 (with a data gap for very low-income countries), whereas it is not useful above a GDP per capita of about $20,000. The corresponding function built using high-income country data is VSL = 8.2474E+3 × (GDP per capita)^∧.6932; it is valid for high-income countries but over-estimates VSL for low- and middle-income countries. The research finds two principal significant differences between the transfer functions modeled using developing-country and high-income-country data, supporting the disaggregated approach. The first of these differences relates to between-country VSL income elasticity, which is 2.478 for the developing country function and .693 for the high-income function; the difference is significant at p < 0.001. This difference was recently postulated but not analyzed by other researchers. The second difference is that the traffic-risk context affects VSL negatively in developing countries and positively in high-income countries. The research quantifies uncertainty in the transfer function using parameters of the non-absolute distribution of relative transfer errors. The low- and middle-income function is unbiased, with a median relative transfer error of −.05 (95% CI: −.15 to .03), a 25th percentile error of −.22 (95% CI: −.29 to −.19), and a 75th percentile error of .20 (95% CI: .14 to .30). The quantified uncertainty characteristics support evidence-based approaches to sensitivity analysis and probabilistic risk analysis of economic performance measures for road-safety investments.     

An empirical assessment of fixed and random parameter logit models using crash- and non-crash-specific injury data

Traditional crash-severity modeling uses detailed data gathered after a crash has occurred (number of vehicles involved, age of occupants, weather conditions at the time of the crash, types of vehicles involved, crash type, occupant restraint use, airbag deployment, etc.) to predict the level of occupant injury. However, for prediction purposes, the use of such detailed data makes assessing the impact of alternate safety countermeasures exceedingly difficult due to the large number of variables that need to be known. Using 5-year data from interstate highways in Indiana, this study explores fixed and random parameter statistical models using detailed crash-specific data and data that include the injury outcome of the crash but not other detailed crash-specific data (only more general data are used such as roadway geometrics, pavement condition and general weather and traffic characteristics). The analysis shows that, while models that do not use detailed crash-specific data do not perform as well as those that do, random parameter models using less detailed data still can provide a reasonable level of accuracy.     

Estimation of the social costs of home injury: a comparison with estimates for road injury

Home injury is thought to constitute a major health burden in most developed countries. However, efforts to address this burden have been hampered by reluctance from outside agencies to interfere with the home environment of individuals, even if it benefits the occupant's safety. This paper outlines cost–benefit evaluation methods established in the transport safety domain applied to home safety to estimate the social cost of unintentional home injury in New Zealand. Estimates of costs imposed on society by home injury can provide an important motivator for initiating research and programmes to reduce home injury risk. Data sources used included mortality data, hospitalisation data and data on minor injuries that required medical treatment, but not hospital admission. We estimated that unintentional home injuries in New Zealand impose an annual social cost of about $NZ 13 billion (about $US 9 billion), which is about 3.5 times the annual social cost of road injury. These estimates provide a rational evidence base for decisions on housing-focused safety regulation or interventions that always carry some cost, and therefore need to be weighed against the benefits of injuries potentially prevented.     

Stated preference in the valuation of interurban road safety

In Chile, as in most less-developed nations, if life savings are valued at all the human capital approach is used in a rather non-consistent fashion. As part of a 5-year research project on the value of transport externalities, a stated preference (SP) experiment was carried out in order to assess the value of a statistical life for Chilean interurban motorways. Interviewees had to choose among different routes for a hypothetical trip, based on the following attributes: travel time, toll charge and level of risk. The results of our experiment show that people were sensitive to the risk variable, thus "stating" a preference for safer routes. Several models were estimated with linear and non-linear utility specifications, and also incorporating the effects of socio-economic variables in a novel and interesting fashion. We were able to estimate subjective values of time consistent with previous values obtained in the country and reasonably looking values (in comparison to Chilean prices and foreign experience) of a statistical life. The paper discusses the experimental design, data collection and analysis, with emphasis on the role of lexicographic individuals that are a feature of SP studies that has not been carefully explored in the literature. We also present our modelling results and compare our derived values (of time and of a statistical life) with values found previously and/or elsewhere.     

Mixed logit analysis of safety-belt use in single- and multi-occupant vehicles

In this paper we demonstrate a modeling approach that can be used to better understand the use of safety belts in single- and multi-occupant vehicles, and the effect that vehicle, roadway and occupant characteristics have on usage rates. Using data from a roadside observational survey of safety-belt use in Indiana, a mixed (random parameters) logit model is estimated. Potentially interrelated choices of safety-belt use by drivers and front-seat passengers are examined. The approach we use also allows for the possibility that estimated model parameters can vary randomly across vehicle occupants to account for unobserved effects potentially relating to roadway characteristics, vehicle attributes, and driver behavior. Estimation findings indicate that the choices of safety-belt use involve a complex interaction of factors and that the effect of these factors can vary significantly across the population. Our results show that the mixed logit model can provide a much fuller understanding of the interaction of the numerous variables which correlate with safety-belt use than traditional discrete-outcome modeling approaches.     

Health-health analysis-an alternative method for economic appraisal of health policy and safety regulation. Some empirical Swedish estimates

Health-health analysis (HHA) focuses on statistical lives themselves as a numeraire. The underlying principle is that the expected gains in health and safety of reduced risks in one area may result in increasing risks somewhere else in society. By reducing one risk other risks may increase due to changed individual behaviour.In addition to this direct effect, another indirect effect will also be present. Expenditure on a particular health policy or safety regulation must be financed in one way or another, which will result in an opportunity cost or income effect leaving less resources for other health and safety promoting activities in society. Thus, we will have an effect that reduces safety and health benefits induced by that income loss. Whether the total net health effect from a specific safety regulation or health policy is positive or negative must be empirically analysed. One way of estimating the income loss that induces one death, which we call the value of an induced death (VOID), is to estimate it as a multiple of the traditional value to avert a statistical death, also named the value of a statistical life (VOSL).A contingent valuation (CV) study eliciting the willingness-to-pay (WTP) for reducing the overall risk of dying was performed as a postal questionnaire in Sweden in 1998. By use of data from this study, it was possible to estimate the VOID and the VOSL in Sweden amounting to SEK116 and SEK20.8 million respectively, indicating that the net health result confined to mortality effects, will be negative (more lives will be lost than saved) if a health policy or safety regulation will cost more than SEK116 million per life saved.     

基于统计能量法的隔声瓦减振性能仿真研究

在水下结构表面敷设隔声去耦材料是应用最广泛也是非常有效的一种提高舰船隐身性能的方法。基于统计能量法开展了隔声瓦对复杂锥柱结构水下振动的影响研究,讨论了隔声瓦敷设方式对复杂锥柱结构水下振动的影响,分析了阻尼损失系数对隔声瓦减振效果的影响。研究表明,隔声瓦敷设方式、阻尼损失系数对隔声瓦减振效果有较大影响:当隔声瓦敷设在结构振动主导传递途径上时,其对传递途径下游结构的振动抑制效果较为明显,而对于振源及传递途径上游结构振动的影响较小;隔声瓦减振效果随敷设密度的增大而增加,随阻尼损失系数的增大而有所降低。     

Estimation of reduced life expectancy from serious occupational injuries in Taiwan

This study assesses the loss of life expectancy and potential working life in Taiwan, between 1986 and 2000, from various types of occupational accidents resulting in mortality or permanent disability. The databases on occupational mortality and permanent disability were obtained from the Bureau of Labor Insurance, with this information then being linked to national death registry data to construct the survival function. A Monte Carlo simulation method was subsequently used to extrapolate the survival rate for up to 600 months, to derive the life expectancy for different types of occupational accidents leading to permanent disability (n=81,249). Based upon the life table for each calendar year, the life expectancy lost by age-gender cohort was also estimated for cases of mortality (n=20,001). In those cases resulting in permanent occupational disability, variations in the expected years of life lost (EYLL) were demonstrated by different occupational injuries, ranging from 7.4 to 13.6 years per case. The overall EYLL through permanent occupational disability is found to be almost identical to that of occupational mortality, with a ratio of 1.04:1. We conclude that permanent disability resulting from occupational injuries has a significant impact on society as a whole.     

International comparison of costs of a fatal casualty of road accidents in 1990 and 1999

The purpose of this study is to assemble information of costs per fatal casualty in traffic accidents, adopted by authorities in different countries. analyse and compare these figures as well as the methods used for estimating these values. A questionnaire was sent to 19 countries from which 11 gave information on cost per fatality and methods of valuation. The costs per fatality, usually defined as direct and indirect costs plus a value of safety per se, are compared both between countries and over time, 1990 and 1999, for each country. The average cost per fatality has increased between 1990 and 1999 (fixed prices) due to both changes in the methodology and changes of valuations. Great Britain, New Zealand, Sweden and the US conduct own willingness-to-pay (WTP) surveys, while the Netherlands and Norway make reviews of these studies. In Finland, the cost per fatality is a combination of the value of lost productivity and the cost of care for an institutionalised disabled person. In Australia, Austria, Germany and Switzerland, the cost per fatality is estimated as a value of lost productivity and an addition of a human cost based on compensation payments or insurance payments. Estimates from recently conducted WTP surveys or meta-analyses are considered in Austria, Finland and Sweden, however, not yet adopted as official values for use in road traffic planning.     

Estimation of useful life in turbines blades with cracks in corrosive environment

Geothermal turbines of 110 MW were installed in the Federal Electricity Commission in Cerro Prieto Mexico, which operating time exceeds 150,000 h. Therefore, the critical components which determine the useful life of the turbine should be evaluated to determine the rehabilitation or replacement of them. The critical components are the blades of the last stage in the steam turbine. It has been observed that different blades of the turbine of 110 MW with cracks presented corrosion products, which resulted in a failure for corrosion fatigue mechanisms. In this paper, it was studied the effect of crack propagation produced in a geothermal turbine blade of the last stage, L-0, which is made of stainless steel AISI 410 exposed to corrosion under a sea water solution. The corrosion phenomena including localized corrosion suffered by the cracking sample were studied through the electrochemical noise technique in current and potential and polarization curves. The tests were conducted on pieces of blades subjected to fatigue. The results indicated that the exposure to the corrosion solution modified the width and the length of the cracks. Using a scanning electron microscopy (SEM), the surface of the crack was observed, showing that the corrosion mechanism produced a significant increment of the velocity of crack propagation and therefore, a decrement of the useful life of the material. This research will allow us to understand the corrosion process in addition to estimate the useful life of the blades when they are subjected to load cycles.     

多输入多输出混合振动试验中正弦与随机信号分离方法

研究了多输入多输出正弦加随机混合振动试验的控制方法,指出混合信号中正弦信号和随机信号的精确分离是提高控制精度的关键因素。提出了具有滤波特性的不相关积分法在时域中识别正弦信号,避免了频域识别的泄露误差问题,详细地推导了将给定频率的正弦信号从混合信号中分离出来的公式;数值计算显示该方法的识别精度达到0.44%。以一悬臂梁作为研究对象建立两输入两输出振动试验系统模型,使用比例均方根控制算法和正弦幅值修正法分别对随机振动和正弦振动进行修正,将随机信号控制在参考谱的±3dB以内,将正弦信号的幅值控制在参考值的±10%以内,满足振动试验要求。     

Social costs of road crashes: An international analysis

This paper provides an international overview of the most recent estimates of the social costs of road crashes: total costs, value per casualty and breakdown in cost components. The analysis is based on publications about the national costs of road crashes of 17 countries, of which ten high income countries (HICs) and seven low and middle income countries (LMICs). Costs are expressed as a proportion of the gross domestic product (GDP). Differences between countries are described and explained. These are partly a consequence of differences in the road safety level, but there are also methodological explanations. Countries may or may not correct for underreporting of road crashes, they may or may not use the internationally recommended willingness to pay (WTP)-method for estimating human costs, and there are methodological differences regarding the calculation of some other cost components.The analysis shows that the social costs of road crashes in HICs range from 0.5% to 6.0% of the GDP with an average of 2.7%. Excluding countries that do not use a WTP- method for estimating human costs and countries that do not correct for underreporting, results in average costs of 3.3% of GDP. For LMICs that do correct for underreporting the share in GDP ranges from 1.1% to 2.9%. However, none of the LMICs included has performed a WTP study of the human costs.A major part of the costs is related to injuries: an average share of 50% for both HICs and LMICs. The average share of fatalities in the costs is 23% and 30% respectively. Prevention of injuries is thus important to bring down the socio-economic burden of road crashes.The paper shows that there are methodological differences between countries regarding cost components that are taken into account and regarding the methods used to estimate specific cost components. In order to be able to make sound comparisons of the costs of road crashes across countries, (further) harmonization of cost studies is recommended. This can be achieved by updating and improving international guidelines and applying them in future cost studies. The information regarding some cost components, particularly human costs and property damage, is poor and more research into these cost components is recommended.     

Unsupervised statistical identification of genomic islands using oligonucleotide distributions with application toVibrio genomes

Vibrio cholerae, Vibrio vulnificus, Vibrio parahaemolyticus and several other relatedVibrio species show distinctly similar two-chromosomal genome organization. However, the modes of pathogenicity are very different among these species, and this is largely attributed to externally acquired genetic elements. We develop some statistical methods to determine these external genetic elements or genomic islands in genomes based on their differential oligonucleotide usage patterns compared to the rest of the genome. Genomic islands identified by these unsupervised statistical methods include integron and pathogenicity islands. After statistical determination of the genomic islands, we investigate their gene contents and their possible association with the pathogenic behaviour of the correspondingVibrio species. These investigations lead to observations that are of evolutionary and biological significance.     

The value of a statistical life in Sweden: Estimates from two studies using the “Certainty Approach” calibration

Stated preference methods using surveys to elicit willingness to pay have been shown to suffer from hypothetical bias and scope/scale bias. Hypothetical bias usually means that willingness to pay is exaggerated in the hypothetical scenario and scope/scale bias means that there is an insensitivity in willingness to pay with regard to the amount of goods or the size of a good being valued. Experimental results in social psychology and economics have shown that only trusting the most certain respondents can potentially solve the problem with hypothetical bias and scope/scale bias. This paper presents the results of two different surveys in Sweden estimating the willingness to pay to reduce traffic mortality risks by only including the most certain respondents. Using the full sample, estimates of the value of a statistical life (VOSL) are $4.2 and $7.3 million. Estimates of VOSL on the subset of the samples only including the most certain respondents are lower and consistent between the two surveys with values of $2.9 and $3.1 million.     

基于DInSAR方法监测南京地表沉降的结果与分析

针对InSAR数据预挑选过程中一直存在着人为的主观性问题,提出了基于相干系数的像对可用性判断因子的概念,利用DInSAR技术对可用性判断因子检测出的可用像对进行处理,获得了南京市区1996年8月到2000年12月间地表沉降结果。通过对沉降结果的时空分析,指出这期间南京地区没有发生持续性的沉陷漏斗,但该地区的地面沉降受地下水位的影响较大,呈现明显的季节性变化。     

Investigating the impact of economic,political, and social factors on augmented reality technology acceptance in agriculture (livestock farming) sector in a developing country

The discussion of factors affecting the acceptance of new technologies in developing countries is very important. The lack of modern technology uses in developing countries, especially in the agricultural (livestock farming) sector, leads to negative effects on the quality and quantity of products and the country loses its ability to compete in the international arena. The main purpose of this study is to investigate the factors affecting on Augmented Reality (AR) technology acceptance in the agricultural (livestock) sector of Iran. In this study, using Meta method, effective factor codes were extracted from AR. The SWARA method was used to weigh the factors affecting the dependent variable based on the opinion of experts. The dependent variable is a qualitative variable that is classified into five levels based on the opinion of experts. We used the multinomial logit model due to the dependent variable is a qualitative variable and has more than two categories. The results showed that, the variables of public participation, and education have a significant effect to accept augmented reality technology at all levels among farmers. The policy recommendations of this research are that councils can play an important role in raising the level of public participation and conveying the demands of the people to the government. To do this, they must receive the necessary training in order to attract public participation. This is possible through training workshops to increase the level of farmers’ awareness.