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In March 2018, an Uber-pedestrian crash and a Tesla's Model X crash attracted a lot of media attention because the vehicles were operating under self-driving and autopilot mode respectively at the time of the crash. This study aims to conduct before-and-after sentiment analysis to examine how these two fatal crashes have affected people's perceptions of self-driving and autonomous vehicle technology using Twitter data. Five different and relevant keywords were used to extract tweets. Over 1.7 million tweets were found within 15 days before and after the incidents with the specific keywords, which were eventually analyzed in this study. The results indicate that after the two incidents, the negative tweets on "self-driving/autonomous" technology increased by 32 percentage points (from 14% to 46%). The compound scores of "pedestrian crash", "Uber", and "Tesla" keywords saw a 6% decrease while "self-driving/autonomous" recorded the highest change with an 11% decrease. Before the Uber-incident, 19% of the tweets on Uber were negative and 27% were positive. With the Uber-pedestrian crash, these percentages have changed to 30% negative and 23% positive. Overall, the negativity in the tweets and the percentage of negative tweets on self-driving/autonomous technology have increased after their involvement in fatal crashes. Providing opportunities to interact with this developing technology has shown to positively influence peoples' perception. • Public perceptions play a crucial role in wide adoption of Autonomous Vehicles (AVs). • Sentiment analysis on 1.7 million tweets was conducted to study public's perceptions. • Tweets on AVs are more negative after their involvement in fatal crashes. • Safety facts on AVs should be publicized to curtail the negativity on this technology. [ABSTRACT FROM AUTHOR]

• The effects of NHTSA vehicle safety ratings on injury outcomes in side impact crashes were examined. • The upper and lower extremities were frequently injured body regions in side impact crashes. • Vehicles rated under new NHTSA criteria had lower average injury severity scores compared to vehicles rated under the old criteria. Introduction: Side impact crash injuries tend to be severe, mainly due to the effects of the mechanism of such crashes. This study addresses the relationship between side impact crash injury severities and side impact safety ratings of the passenger cars involved in such crashes. It is motivated by the lack of research on side impact safety ratings in relation to the real-world crash outcomes. Method: Analysis of Crashworthiness Data System's (CDS) data show the head and thorax are the most common regions of impact of severe injuries, while the neck is the least. Irrespective of body regions, higher-rated vehicles were found to provide better occupant protection to both younger and older driver age groups. Assessment based on injury severity score (ISS) indicates that higher-rated vehicles have an overall lower average ISS compared to lower-rated vehicles. Results: Ultimately, this study shows that vehicles rated with National Highway Traffic Safety Administration's (NHTSA) new criteria had lower average ISS compared to vehicles rated under the old criteria. The 2011 NHTSA side impact rating criteria being relatively new, it has very few crashes to draw meaningful statistically significant conclusions. However, this paper establishes the fact that vehicles with higher star ratings (under experimental conditions) indeed offer increased occupant protection in the field conditions. Practical applications: Previous studies have found that safety was given priority while buying new vehicles. However, people associated vehicle safety with technologies and specific safety features rather than the vehicle's crash test results or ratings (Koppel, Charlton, Fildes, & Fitzharris, 2008). The results from this study provide a point of reference for safety advocates to educate the drivers about the importance of considering vehicle safety ratings during a vehicle purchase. [ABSTRACT FROM AUTHOR]

Public perceptions play a crucial role in wider adoption of autonomous vehicles (AVs). This paper aims to make two contributions to the understanding of public attitudes toward AVs. First, we explore opinions regarding the perceived benefits and challenges of AVs among vulnerable road users – in particular, pedestrians and bicyclists. Second, the paper evaluated whether interaction experiences with AVs influence perceptions among vulnerable road users. To explore this, we examined survey data collected by Bike PGH, a Pittsburgh based organization involved in programs to promote safe mobility options for road users. Analysis of the data revealed that respondents with direct experience interacting with AVs reported significantly higher expectations of the safety benefits of the transition to AVs than respondents with no AV interaction experience. This finding did not differ across pedestrian and bicyclist respondents. The results of this study indicate that as the public increasingly interacts with AVs, their attitudes toward the technology are more likely to be positive. Thus, this study recommends that policy makers should provide the opportunities for the public to have interaction experience with AVs. The opportunities can be provided through legislation that allows auto manufacturers and technology industries to operate and test AVs on public roads. This interactive experience will positively affect people's perceptions and help in wider adoption of AV technology. • Public perceptions play a crucial role in wider adoption of autonomous vehicles (AVs). • As the public increasingly interacts with AVs, their attitudes toward the technology are more likely to be positive. • We recommend policy makers to pass legislation that will authorize testing and operation of AVs on public roads. • Interaction experience with AVs will positively affect people's perceptions and help in wider adoption of the technology. [ABSTRACT FROM AUTHOR]

Motor vehicles with advanced safety technologies are rapidly entering the marketplace and the impact of new features are transforming safety on roadways. Among the several safety related technologies currently available in the market, this paper aims to forecast the reduction in crashes with gradual adoption of vehicles with lane departure prevention (LDP) technology. Crash data for the state of Alabama from 2014 to 2016 were used to evaluate the safety benefits of LDP technology. In Alabama, 75% of single-vehicle crashes are the result of lane departure. A 20% effective LDP system implies, whereby an LDP system would prevent a vehicle from exiting a roadway on 20% of applicable instances, would reduce 2.7% and 16.4% of the relevant single-vehicle lane departure (SVLD) crashes by 2020 and 2045 respectively. With increase in the effectiveness of the technology, a greater reduction in crashes was observed. With 100% effectiveness, this technology can prevent 66.5% of SVLD crashes by year 2045. This study presents the first estimations of the number of crashes that could be reduced using LDP and therefore could have significant impacts on public and industry adoption rates of the technology. The results of this study influence policy making and regulatory approaches to improving motor vehicle safety and further recommend education and outreach activities to increase awareness on the benefits of LDP technology. • This study forecasts how gradual adoption of vehicles with lane departure prevention (LDP) technology can reduce crashes. • By 2020, 2.7% of single-vehicle lane departure crashes could be avoided if 8.5% of the fleet has LDP with 20% effectiveness. • With increase in the effectiveness of LDP technology, the reduction in relevant crashes increased. • If the LDP system is 100% effective by 2045, 66.5% of the single-vehicle lane departure crashes can be prevented. [ABSTRACT FROM AUTHOR]

Highlights • Road, weather, and geometric characteristics have a similar effect on crash injury severity of at-fault and not at-fault drivers. • Driver age, gender, and physical condition influence crash injury severity of not at-fault drivers. • Vehicle type, and, the number and type of traffic rule violations influence crash injury severity of not at-fault drivers. • Motorcyclists and drivers 70 years or older are observed to be the most vulnerable road users. Abstract This paper examines and compares the effect of selected variables on driver injury severity of, both, at-fault and not at-fault drivers. Data from the Highway Safety Information System (HSIS) for the state of North Carolina was used for analysis and modeling. A partial proportional odds model was developed to examine the effect of each variable on injury severity of at-fault driver and not at-fault driver, and, to examine how each variable affects these two drivers’ injury severity differently. Road characteristics, weather condition, and geometric characteristics were observed to have a similar effect on injury severity in a crash to at-fault and not at-fault drivers. Age of the driver, physical condition, gender, vehicle type, and, the number and type of traffic rule violations were observed to play a significant role in the injury severity of not at-fault drivers when compared to at-fault drivers in the crash. Moreover, motorcyclists and drivers 70 years or older are observed to be the most vulnerable road users. [ABSTRACT FROM AUTHOR]

The media continues to be a prominent and widely embraced channel for obtaining information on various topics, exerting considerable influence in shaping public opinions. This holds particularly true for the realm of automated vehicles (AVs), as the media consistently covers developments in this field, encompassing both positive aspects such as technological advancements, as well as negative occurrences like incidents involving self-driving cars colliding with pedestrians. The objective of this study was to utilize sentiment analysis techniques to evaluate the portrayal of AV technology in media news coverage. Data was retrieved from Sprinklr using keywords that are often associated with AVs. Over 1.7 million articles were collected on the keywords for relevant articles published between May 1, 2015 to May 24, 2021. Sentiment analysis was carried out on the cleaned data using three different models – VADER, TextBlob, and NRCLex. The sentiment analysis was separately conducted on the title and text of the articles. 2018 recorded the highest number of news articles on the AV technology. The number of negative sentiments in the title of articles published on the web in 2018 increased 12 times compared to the previous year. The negativity induced in 2018 in the news media did not continue in the next year, which explains that the technology experienced short term effects from the negative incidents associated with its early development. The news articles were also found to have subjectivity from the authors in the article text. The findings are expected to stimulate debates among industry players on how to bring the media along the journey of the development and eventual full deployment of AVs. • The negative sentiment is short lived in the news media articles. • Positivity and trust were the strongest sentiments in the media articles text. • Authors of the news media articles incorporated their subjectivity into the text. [ABSTRACT FROM AUTHOR]

The objective of this research is to identify factors associated with crashes due to overcorrection or oversteering of vehicles. Crash data was collected from 2011 to 2013 for the State of North Carolina in the United States. Logistic regression modeling was used to analyze crash data because of the dichotomous nature of the dependent variable (overcorrection or oversteering). The crash involvement due to overcorrection or oversteering of a vehicle decreased as the age of the driver increased. Drivers are 2.22 times more likely to overcorrect or oversteer when ill, 3.44 times more likely to overcorrect or oversteer when under fatigue, and 1.61 times more likely to overcorrect or oversteer when fallen asleep compared to normal physical conditions. Overall, driver characteristics and speed limit tend to play a major role in overcorrection or oversteering of vehicles. Programs to reduce impaired driving might help in the reduction of overcorrection or oversteering related crash fatalities or injuries. Additionally, training and driver education programs focusing on identified factors associated with crashes due to overcorrection or oversteering of vehicles will benefit drivers on how to respond during emergency or panic situations. [ABSTRACT FROM AUTHOR]

Education, enforcement and engineering countermeasures are implemented to make road users comply with the traffic rules. Not all the traffic rule violations can be addressed nor countermeasures be implemented at all unsafe locations, at once, due to limited funds. Therefore, this study aims at ranking the traffic rule violations resulting in crashes based on individual ranks, such as 1) frequency (expressed as a function of the number of drivers violating a traffic rule and involved in crashes), 2) crash severity, 3) total crash cost, and, 4) cost severity index, to assist transportation system managers in prioritizing the allocation of funds and improving safety on roads. Crash data gathered for the state of North Carolina was processed and used in this study. Variations in the ranks of traffic rule violations were observed when individual ranking methods are used. As an example, exceeding authorized speed limit and driving under the influence of alcohol are ranked 1st and 2nd based on crash severity while failure to reduce speed and failure to yield the right-of-way are ranked 1st and 2nd based on frequency. To minimize the variations and capture the merits of individual ranking methods, four different composite ranks were computed by combining selected individual ranks. The computed averages and standard deviations of absolute rank differences between composite ranks is lower than those obtained from individual ranks. The weights to combine the selected individual ranks have a marginal effect on the computed averages and standard deviations of absolute rank differences. Combining frequency and crash severity or cost severity index, using equal weights, is recommended for prioritization and allocation of funds. [ABSTRACT FROM AUTHOR]

• States were scored to assess safety standards for children traveling in Transportation Network Company (TNC) vehicles. • The scoring was based on two parameters: clarity and stringency in the state child car seat laws for TNCs. • The results of this study suggest that all states could enhance the safety of children traveling in TNC vehicles by focusing on clarity and stringency of child car seat laws. • This study will help key stakeholders to better understand legal issues pertaining to the use of child car seats in TNC vehicles, identify states with lower standards for child safety purposes in TNCs, and comprehensively address the issue. Introduction: As transportation network companies (TNC) are on the rise, assessing the safety of children traveling in these vehicles is imperative. For this reason, this study developed and adopted a scoring system to assess states' safety standards for children traveling in TNC vehicles. Methods: The scoring was based on two parameters pertaining to child car seat laws for TNCs: clarity and stringency. For each parameter, three criteria that could impact child safety in TNC vehicles were formulated. If a state met a certain criterion it got 1 point and 0 otherwise. The authors gathered all the necessary information by reviewing state statutes in Nexus Uni, a legal research database. These reviews took place between December 2019 and October 2020, and this study evaluated state laws in effect on October 28, 2020. Results: During this assessment, the authors observed a lack of clarity in state child car seat laws, which could compromise safety of children traveling in TNC vehicles. For clarity of laws, Georgia and Indiana received the highest scores (3 out of 3 points), while 16 states scored only 1 point, which was the lowest score in this category. In terms of stringency of laws, Pennsylvania received the highest score (3 out of 3 points), while Indiana scored the least (0 points). Conclusions: Besides one state (Oregon), all other states defined TNCs in their state laws. All states except for Indiana and Washington required child car seats in TNC vehicles. The responsibility for child car seat use was clearly defined in 35 states. The fine for child car seat violation was $50 or more in 28 states. Practical Application: This study will help TNCs, policymakers, and stakeholders identify states that need to improve their standards for child safety in TNC vehicles, and comprehensively address the issue. [ABSTRACT FROM AUTHOR]