When the right-turn vehicles share the same phase with pedestrians on divided lanes at intersection, the stopped buses or medium-size vehicles that closed to the right-turn vehicles would block the view of drivers and pedestrians from the far-side of crosswalk. This paper aims at analyzing the changes of lag/gap acceptance behavior with/without considering sight obstruction and the headway of following right-turn vehicles by video observation. Cumulative Weibull distribution function was used to estimate parameters of lag/gap acceptance probabilities. The result showed that right-turn drivers tend to accept a smaller lag/gap with restricted sight, and it would lead to more potential conflicts between right-turn vehicles and pedestrians. However, larger headway of following right-turn vehicles with sight obstruction may result in delay and reduced capacity in right-turn lanes. This study will hopefully improve the understanding of the relationship between visibility and pedestrian-vehicle conflicts. 1. Introduction Critical situations such as vehicle-pedestrian conflicts at signalized intersection are complex and serious, especially when pedestrians share the same phase with right-turning vehicles. And it draws significant attention by many scholars. At a signalized intersection without protected right-turn phase, right-turning vehicles and pedestrians have to share the same phase. In general, vehicles should yield to pedestrians in such cases, but in reality, drivers prefer smaller gaps and will not yield to pedestrians because of some situational factors like speed of vehicles/pedestrians, the volume of vehicles and pedestrians, the behavior of right-turning vehicles and crossing pedestrians, and geometric of the intersection and the delay of pedestrians. Driver and pedestrian behavior have already been investigated by introduction of some pedestrian traffic facilities [1] and some models which can describe certain behavioral tasks [2–4]. To an identified behavior, lags/gaps acceptance behavior, various functions were used to estimate in different conditions in previous literatures. Siegloch developed the linear regression model and defined the parameters in this model to analyze gap acceptance [5]. The method is straightforward for gap acceptance, but the probability distribution of gap acceptance was ignored. Then, the logistic regression model was proposed. Cooper and Zheng used logistic regression method to analyze “sequence” gap acceptance between distracted and not distracted [6]. A Bayesian and Bootstrap approaches were used to propose a gap
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