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It is necessary to analyze pedestrian behavior at crossings to improve their safety and mobility. Mid-block pedestrian crossings are structures that facilitate the mobility of pedestrians, safeguarding them from vehicular traffic; however, illegal crossing by pedestrians is an everyday occurrence and represents a risk to their safety. The purpose of this study is to evaluate the relationship between different human and road factors and the decision to illegally cross signalized mid-block crossings. Several human factors such as age, gender, waiting time in traffic light, use of the pushbutton and individual or group crossing, as well as road characteristics such as the length of traffic light phase, length of crossing, and vehicular volume were analyzed. To collect information about these variables, this study recorded a one-hour video in six selected crosswalks within the Montes de Oca County in Costa Rica. A total of 1,707 crossings were recorded, 10.6 % of which corresponded to instances of illegal crossing. After applying a logit model, this research found out that traffic volume, pedestrian red-light time, waiting time, vehicle illegal crossing and group crossings reduced the probability of violations by pedestrians. On the other hand, minimum traffic light time and crossing length increased the possibility of pedestrian illegal crossings. This study concluded that the traffic light cycle is an important variable that must be rigorously analyzed to ensure pedestrian’s compliance with traffic lights, which will improve the safety of the pedestrian mid-block crossings. Resumen Es necesario analizar el comportamiento de los peatones en los cruces para mejorar su seguridad y movilidad. El propósito de este estudio es evaluar la relación entre diferentes factores humanos y viales y la decisión de cruzar ilegalmente cruces señalizados a mitad de cuadra. Se analizaron varios factores humanos como la edad, el género, el tiempo de espera en el semáforo, el uso del pulsador y el cruce individual o grupal, así como características de la vía como la duración de la fase del semáforo, la longitud del cruce y el volumen vehicular. Para recopilar información sobre estas variables, se grabó video en seis pasos de peatones seleccionados dentro del cantón de Montes de Oca en Costa Rica. Se registraron un total de 1 707 cruces, de los cuales el 10,6 % correspondieron a cruces ilegales. Después de aplicar un modelo logit, se encontró que el volumen de tráfico, el tiempo en rojo, el tiempo de espera, el cruce ilegal de vehículos y los cruces grupales redujeron la probabilidad de infracciones. Por otro lado, el tiempo mínimo del semáforo y la longitud del cruce aumentaron la posibilidad de cruces peatonales ilegales. Se concluyó que el ciclo del semáforo es una variable importante que debe ser analizada rigurosamente para garantizar el respeto a los semáforos por parte de los peatones, lo que mejorará la seguridad de los cruces peatonales a mitad de cuadra.

The purpose of this article was to investigate driver's speed behaviors during the yellow-light period and how satisfied they were at the intersections under the Red-Light Cameras (RLC) project. The survey data was collected before the project implementation and 3 months after the project began. The data was analyzed by calculating the correlation between the distances from the intersection and the drivers’ speeds entering the intersections during the yellow signal. In addition, the satisfaction was evaluated with 400 samples based on the questionnaire conducted when the RLC project was ongoing. The results showed that drivers speeded up significantly during the yellow signal when they were approaching the stop line, both at the intersections under the project and at the other intersection. Besides, it was found that the speed during the yellow light reduced significantly at all distances, i.e, 14-40% (6.5-22 km/hr.), resulting in 20-meter reduction of the maximum length of movement during the yellow signal period, compared to an unchanged distance at the control intersection. The analytical results corresponded to the 56% reduction of red-light runners after RLC project began. As for the drivers’ satisfaction towards the RLC project, it was found that the majority (64%) showed positive satisfaction, and that 67% reported that the project resulted in speed reduction. In addition, some variables were found to significantly correlate with the attitudes towards RLC project. The study's findings can be used as references, and the approach can be applied in other locations to prevent traffic collisions at intersections.

The traditional way to evaluate pedestrian safety is a reactive approach using the data at an aggregate level. The objective of this study is to develop real-time safety models for pedestrian red-light running using the signal cycle level traffic data. Traffic data for 464 signal cycles during 16 h were collected at eight crosswalks on two intersections in the city of Nanjing, China. Various real-time safety models of pedestrian red-light running were developed based on the different combination of explanatory variables using the Bayesian Poisson-lognormal (PLN) model. The Bayesian estimation approach based on Markov chain Monte Carlo simulation is utilized for the real-time safety models estimates. The models’ comparison results show that the model incorporated exposure, pedestrians’ characteristics and crossing maneuver, and traffic control and crosswalk design outperforms the model incorporated exposure and the model incorporated exposure, pedestrians’ characteristics, and crossing maneuver. The result indicates that including more variables in the real-time safety model could improve the model fit. The model estimation results show that pedestrian volume, ratio of males, ratio of pedestrians on phone talking, pedestrian waiting time, green ratio, signal type, and length of crosswalk are statistically significantly associated with the pedestrians’ red-light running. The findings from this study could be useful in real-time pedestrian safety evaluation as well as in crosswalk design and pedestrian signal optimization.

Detection-Control System (D-CS), a dilemma-zone protection technology developed by the Texas Transportation Institute (TTI) for isolated rural high-speed intersections, was evaluated in a before and after study. By detecting vehicle lengths and speeds at locations 800ft to 1000ft (244 m to 305 m) upstream of the intersection; D-CS monitors the approaching vehicles on a lane-by-lane basis and assigns different weights to trucks and cars based on vehicle length. When processing the real time traffic data, D-CS predicts the best time to end the major approach green phase. This paper looks at eight sites in four states for which the United States Federal Highway Administration (FHWA) deployed D-CS. At each site, one week's worth of cycle-by-cycle traffic and video data were collected to assess the effectiveness of D-CS. The analysis results showed that on average, after activation of the D-CS technology, the frequencies of red-light violations, max-outs, and number of vehicles trapped in dilemma zone were reduced by 68%, 9%, and 57% respectively. Based on the results obtained, the research team concluded that larger scale deployment of this technology can improve safety of thousands of signalized intersections that have the desired geometric and traffic conditions under which D-CS is expected to yield a high benefit to cost ratio.