Offsetting or Enhancing Behavior: An Empirical Analysis of Motorcycle Helmet Safety Legislation

This study uses state‐level panel data from a 33‐year period to test the hypotheses of offsetting and enhancing behavior with regards to motorcycle helmet legislation. Results presented in this article find no evidence of offsetting behavior and are consistent with the presence of enhancing behavior. State motorcycle helmet laws are estimated to reduce motorcycle crashes by 18.4% to 31.9%. In the absence of any behavioral adaptations among motorcyclists mandatory helmet laws are not expected to have any significant impact on motorcycle crash rates. The estimated motorcycle crash reductions do not appear to be driven by omitted variable bias or nonclassical measurement error in reported crashes. Overall, the results strongly suggest that mandatory helmet laws yield significant changes in motorcycle mobility in the form of reduced risk taking and/or decreased utilization.     

Effects of Increased Auto Safety Belt Use Levels on Fatalities

To reduce the annual toll of highway deaths, more than 30 states have passed laws mandating the use of safety belts. All have been effective at raising safety belt use; equipped with different provisions and enforced with unequal care, however, they have done so to different degrees. The article estimates the relationship between attained belt use and fatalities averted. Monthly 1982-1986 fatality, collision, belt use, and other data from 64 areas in nine states were collected, then analyzed using a Poisson multiple regression model. The analysis indicates that an increase in belt use from 14-40% averts about 13% of fatalities; a more pronounced increase to 50% averts about 18%. An increase from 50-75% averts about 16% of remaining fatalities. Three significant conclusions emerge. First, previous estimates appear to have understated, in general, the overall effectiveness of belt use laws. Second, the benefits of programs to boost safety belt use in this country from its current level of about 50% to up to 75%, estimated on the basis of more direct evidence from U.S. data than previously available, appear to be very large. Third, Poisson and other multiple regression models including explicit allowance for other causal factors can usefully complement other statistical approaches in traffic safety studies.     

Risk Compensation and Bicycle Helmets

This study investigated risk compensation by cyclists in response to bicycle helmet wearing by observing changes in cycling behavior, reported experience of risk, and a possible objective measure of experienced risk. The suitability of heart rate variability (HRV) as an objective measure of experienced risk was assessed beforehand by recording HRV measures in nine participants watching a thriller film. We observed a significant decrease in HRV in line with expected increases in psychological challenge presented by the film. HRV was then used along with cycling pace and self‐reported risk in a field experiment in which 35 cyclist volunteers cycled 0.4 km downhill, once with and once without a helmet. Routine helmet users reported higher experienced risk and cycled slower when they did not wear their helmet in the experiment than when they did wear their helmet, although there was no corresponding change in HRV. For cyclists not accustomed to helmets, there were no changes in speed, perceived risk, or any other measures when cycling with versus without a helmet. The findings are consistent with the notion that those who use helmets routinely perceive reduced risk when wearing a helmet, and compensate by cycling faster. They thus give some support to those urging caution in the use of helmet laws.     

Predictors of Parental Risk Perceptions: The Case of Child Pedestrian Injuries in School Context

The objective of this article is to explore the factors that influence parental risk perceptions of child pedestrian injuries in the elementary school context. Parents (n= 193) from six different schools responded to a questionnaire on road safety, including a measure of their risk perception. Results of bivariate analyses show that eight variables are significantly related to risk perception. Environmental variables, as we measure them, were not significant, contrary to our initial hypotheses. Only three variables, parent's gender, perceived primary source of danger, and sense of control remained significant in OLS regression analyses (adjusted R² of 0.16, F= 9.27; p= 0.00). Since parents’ perceptions of road risks are an important factor in their road safety practices and in their choice of transportation mode used for their child's journey to school, our analysis elucidates factors underlying these choices. Our results can help decisionmakers to design traffic injury prevention measures and to promote physical activity through the use of active modes of transport.     

The Health Impact of Mandatory Bicycle Helmet Laws

This article seeks to answer the question whether mandatory bicycle helmet laws deliver a net societal health benefit. The question is addressed using a simple model. The model recognizes a single health benefit—reduced head injuries—and a single health cost—increased morbidity due to foregone exercise from reduced cycling. Using estimates suggested in the literature on the effectiveness of helmets, the health benefits of cycling, head injury rates, and reductions in cycling leads to the following conclusions. In jurisdictions where cycling is safe, a helmet law is likely to have a large unintended negative health impact. In jurisdictions where cycling is relatively unsafe, helmets will do little to make it safer and a helmet law, under relatively extreme assumptions, may make a small positive contribution to net societal health. The model serves to focus the mandatory bicycle helmet law debate on overall health.     

Mandatory Belt Use and Driver Risk Taking

A study of driver behavior before and after a mandatory seat belt use law in Newfoundland found that the benefits of such legislation are not reduced by riskier driving, as has been suggested by some theorists. On average, belt use in Newfoundland increased from 16% of drivers before the law to 77% after the law. At the same time, the quality of driving changed very little when compared to control groups of Nova Scotia drivers, who were not subject to the law and whose belt use rates did not change. In only one situation did Newfoundland drivers differ from the control group in Nova Scotia: after the belt law, drivers in Newfoundland became relatively more cautious (slower) in their speeds on four-lane expressways. These data confirm the results of earlier less controlled studies that also found no changes in driving behavior following nonvoluntary changes in occupant protection. Since the "risk-compensation" hypothesis predicts such changes, it seems to have no merit in explaining changes in fatalities and injuries after occupant protection legislation.     

QRA Model‐Based Risk Impact Analysis of Traffic Flow in Urban Road Tunnels

Road tunnels are vital infrastructures providing underground vehicular passageways for commuters and motorists. Various quantitative risk assessment (QRA) models have recently been developed and employed to evaluate the safety levels of road tunnels in terms of societal risk (as measured by the F/N curve). For a particular road tunnel, traffic volume and proportion of heavy goods vehicles (HGVs) are two adjustable parameters that may significantly affect the societal risk, and are thus very useful in implementing risk reduction solutions. To evaluate the impact the two contributing factors have on the risk, this article first presents an approach that employs a QRA model to generate societal risk for a series of possible combinations of the two factors. Some combinations may result in F/N curves that do not fulfill a predetermined safety target. This article thus proposes an “excess risk index” in order to quantify the road tunnel risk magnitudes that do not pass the safety target. The two‐factor impact analysis can be illustrated by a contour chart based on the excess risk. Finally, the methodology has been applied to Singapore's KPE road tunnel and the results show that in terms of meeting the test safety target for societal risk, the traffic capacity of the tunnel should be no more than 1,200 vehs/h/lane, with a maximum proportion of 18% HGVs.     

A Risk-Based Method for Modeling Traffic Fatalities

We describe a risk-based analytical framework for estimating traffic fatalities that combines the probability of a crash and the probability of fatality in the event of a crash. As an illustrative application, we use the methodology to explore the role of vehicle mix and vehicle prevalence on long-run fatality trends for a range of transportation growth scenarios that may be relevant to developing societies. We assume crash rates between different road users are proportional to their roadway use and estimate case fatality ratios (CFRs) for the different vehicle-vehicle and vehicle-pedestrian combinations. We find that in the absence of road safety interventions, the historical trend of initially rising and then falling fatalities observed in industrialized nations occurred only if motorization was through car ownership. In all other cases studied (scenarios dominated by scooter use, bus use, and mixed use), traffic fatalities rose monotonically. Fatalities per vehicle had a falling trend similar to that observed in historical data from industrialized nations. Regional adaptations of the model validated with local data can be used to evaluate the impacts of transportation planning and safety interventions, such as helmets, seat belts, and enforcement of traffic laws, on traffic fatalities.     

Toward an understanding of consumers’ perceptions of food labels

This study examines the factors that influence consumers’ perceptions or beliefs about food labels. The results indicate that health and diet related attitudes, special diet status, perceived importance of product attributes like nutrition and ease of preparation, race, gender, income, and body mass index are important factors affecting consumers’ perceptions and beliefs about label use. Understanding the type of consumers who have these perceptions and beliefs as well as the factors that influence these beliefs and perceptions is crucial for designing effective marketing and nutrition education campaigns.     

National cultures and safety orientation: A study of seafarers working for Norwegian shipping companies

Up to now, little work has been conducted on safety in relation to national culture. This paper examines the association between national culture and the safety orientation of seafarers on Norwegian-owned vessels. Safety orientation is the result of cultural, organizational, and contextual factors that create attitudes and behaviours that in turn influence safety. In this study a safety culture/orientation questionnaire was designed and used to determine risk and safety characteristics. Survey data was collected from 2,558 seafarers from 27 countries. The sample used consisted of seafarers from the 10 countries for which there were more than 10 respondents. Five national (cultural) characteristics were calculated using Hofstede's Value Survey Model 94. Multivariate analysis of variance revealed that (a) the number of nationalities represented on a vessel was related to their attitude towards safety issues, such that two-nation vessels obtain relatively negative scores regarding these issues, and (b) national culture was related to safety culture, such that high power distance, high uncertainty avoidance, and high individualism were positive for safety. The implications of these findings for practice and future research are discussed.     

Performance Management and Occupational Safety

Instructional techniques used by the author to teach a performance management (PM) approach to occupational safety are reviewed. Post-workshop safety programs were implemented at several plants without consultation from a PM specialist; however, the PM strategies were not evaluated systematically unless they targeted vehicle saftey belt use. Thus, a Case is made from starting with a safety belt program, not only because such programs can reduce the most significant cause of lost work time (ie.e., the vehicle crash), but also because the behavior change success of a corporate safety belt program can be readily assessed by company personnel and therefore reinforce the PM approach to occupational safety.     

Exposure to Traffic and Risk of Hospitalization Due to Injuries

Research on the risk of motor vehicle injuries and their relationship with the amount of travel has been only partially analyzed. The few individual exposure assessments are related to very specific subsets of the driving and traveling populations. This study analyzes the relationship between kilometers traveled and hospitalization due to motor vehicle injuries. Twelve thousand three hundred and sixty nine Spanish university graduates from the Seguimiento Universidad de Navarra multipurpose cohort study were evaluated. They had not been hospitalized due to motor vehicle injuries at baseline and were followed up to eight years. Biannual questionnaires allowed for self‐reporting of kilometers traveled in motor vehicles, together with incidence of hospitalization. Covariates in the Cox regression models included age and gender and baseline use of safety belt while driving, driving a vehicle with driver‐side airbag, driving a motorcycle, and drinking and driving. There were 49,766 participant‐years with an average yearly travel of 7,828 km per person‐year. Thirty‐six subjects reported a first hospitalization event during this time. The adjusted hazard ratio per additional kilometer traveled was 1.00005 (95% confidence interval 1.000013 to 1.000086). Even the smallest of reductions in the amount of kilometers traveled (from an average of 3,250 km per year to 1,000) has a statistically significant protective effect on the likelihood of sustaining hospitalization due to motor vehicle injury (aHR 0.9, 95% CI 0.78 to 0.98). In light of current policies aimed to reduce motorized traffic due to environmental concerns, it may be appropriate to consider the additional health benefit related to reductions in injuries.     

城市路网运输性能退化成本评估模型

路网的运行受到诸多因素的影响而使得路网运输性能发生退化,分析了路网运输性能退化的影响因素和作用机理,给出了路网运输性能退化及退化的极端情况路段失效的成本分析过程框架.基于BPR路阻函数和用户均衡分配理论分析路网运输性能退化的成本函数,建立了拥堵情况下城市路网路段失效的成本评估模型.最后,通过实例分析了路网运输性能退化对出行成本影响的变化规律,给出了路网运输性能退化的极端情况路段失效成本评估的具体过程,研究表明路网运输性能退化对出行成本具有很大的影响,二者成显著的正相关关系.     

建设项目绿色创新努力及利他偏好诱导

建设项目绿色创新有赖于相关参与方的协同努力,利他偏好对合作参与方的自身努力与合作努力行为决策存在影响,通过建立项目绿色创新中主导方与成员方间的Stackelberg博弈模型,分析"分散—分散"与"集中—集中"两种决策结构情境下考虑利他偏好影响的绿色创新努力行为决策,得到以下结论：（1）在大多数情形下,利他偏好会对建设项目参与方努力行为产生正面作用,但具体影响程度与影响方向受所处的决策结构情境以及参与方间的利他偏好差异影响;（2）收益分配等因素影响参与方的两类努力行为决策,但是参与方间的利他偏好差异变化会改变收益分配对努力行为的影响方向,即利他偏好通过收益分配间接影响参与方努力决策;（3）收益的公平分配、适度的努力成本以及社会声誉激励可对利他行为形成诱导。由此,在利他偏好之于努力行为决策影响的研究中考虑情境及相关因素的影响,将使得结论更贴近现实。     

Motivating Auto Safety Belt Wearing in Industrial Settings:

Employees at an industrial plant (n = 141) participated in 40-minute safety belt "awareness sessions," which for some groups included opportunities to sign buckle up pledge cards. The duration of the pledge period was one week, one month, or three months for different groups of approximately 35 employees each. The awareness sessions, alone or with pledge cards, yielded a three-fold increase in safety belt use (from approximately 20% to 60%), which was sustained over the 13 weeks of post-session observation. While most employees signed pledge cards regardless of the pledge duration, pledging did not produce greater increases in safetey belt use than the awareness sessions without pledge cards. Further, pledge duration had no differential effect on likelihood of signing, or subsequent compliance. The usual white/blue-collar difference was found, with white-collar employees showing higher rates of safety belt use throughout the study. The results suggest strongly that an "intrinsic control" strategy of raising awareness and increasing personal commitment to buckle up can substantially increase safety belt use. The application of this approach as a cost-effective component of an overall program to increase safety belt use is discussed.     

对外直接投资对母国收入差距的影响效应——基于跨国面板数据的研究

本文将企业异质性理论引入内生增长模型，讨论对外直接投资（OFDI）对母国收入差距的影响机理，并基于1981~2015年85个国家（地区）的面板数据，同时运用静态模型与动态模型验证了二者间存在"倒U型"关系，即随着对外直接投资强度的提升，母国收入差距呈现先扩大再缩小的态势；OFDI一方面通过促进母国的技术进步与产业结构升级、挤出部分国内投资等渠道加剧了收入不平等程度，另一方面以推动母国的金融发展与教育拓展等方式对收入差距产生削减效果；OFDI对收入差距的影响在不同经济发展水平、不同地理区位的国家中具有异质性：当人均GDP小于5767.53美元时，对外直接投资强度显著地扩大了母国收入差距，当人均GDP超过5767.53美元时，二者之间不存在显著的线性关系；欧洲国家的OFDI与收入差距之间呈现出"倒U型"关系，美洲、亚洲国家的OFDI促进了母国收入差距的扩大，非洲国家的OFDI对收入差距无显著影响；此外，OFDI对母国收入差距的影响具有跨期效应，随着时间推移与OFDI存量增加，其间接效应的边际效果有所减弱。     

委托人代理人竞争力与合约报酬分配均衡

委托人代理人竞争力是委托代理合约设计与报酬分配的重要决定因素。构建的委托人代理人竞争力合约模型表明:①委托人代理人竞争力独自决定各自的固定收入报酬,并与竞争力投入策略、二阶成本因素和代理人风险偏好因素共同决定剩余收入分配;②委托人代理人竞争力及其投入策略反应对合约设计、合约产出、剩余收入分配、竞争力投入比例的影响受合约报酬偏好、二阶成本和风险偏好因素的约束;③委托人代理人竞争力及其投入策略的非对称性是剩余收入分配冲突产生的根源,也是合约动态调整、报酬分配变动与合约有效性变化的重要原因;④调控合约报酬分配应该着力调节委托人代理人竞争力关系和策略反应。     

CREDIT,WAGES, AND BANKRUPTCY LAWS

We analyze how bankruptcy laws affect the general equilibrium interactions between credit and wages. Soft laws reduce the frequency of liquidations and thus ex post inefficiencies, but they worsen credit rationing ex ante. This hinders firm creation and thus depresses labor demand. Rich agents who need few outside funds can invest even if creditor rights are weak. Hence, they favor soft laws that exclude poorer agents from the credit market and reduce the competition for labor. Such laws can generate greater utilitarian welfare than under perfect contract enforcement: By barring access to credit to some agents, soft laws lower wages, which increases the pledgeable income of richer agents and decreases the liquidation rates they must commit to. When they induce strong credit rationing, however, soft laws are Pareto‐dominated by tougher laws combined with subsidies to entrepreneurs. (JEL: D82, G33, K22)     

农村公路网发展规模的影响因素分析

影响农村公路网规模发展的因素很多,这些因素相互之间不仅存在着复杂的内在联系,而且每个因素的影响作用也不相同,笔者提出了以灰色关联度为基础的定量分析方法,找出影响农村公路网发展规模的主要因素,以便对农村公路网规模建设进行科学预测。     

Socioeconomic Determinants of Health- and Food Safety-Related Risk Perceptions

Individual and societal perceptions of food-related health risks are multidimensional and complex. Social, political, psychological, and economic factors interact with technological factors and affect perceptions in complex ways. Previous research found that the significant determinants of risk perceptions include socioeconomic and behavioral variables. Most of these past results are based on two-way comparisons and factor analysis. The objective of this study was to analyze the significance of socioeconomic determinants of risk perceptions concerning health and food safety. A multivariate approach was used and the results were compared with earlier bivariate results to determine which socioeconomic predictors were robust across methods. There were two major findings in this study. The first was that the results in the multivariate models were generally consistent with earlier bivariate analysis. That is, variables such as household income, number of children, gender, age, and voting preferences were strong predictors of an individual's risk perceptions. The second result was that the gender of the respondent was the only variable found to be robust across all three classes of health and food safety issues across two time periods.