Empirical Research On The Vehicle Restriction Policy Implementation Results

The restriction policies is widely implemented at home and broad while the effectiveness is controversial.The objective evaluation is based on the analysis of road traffic flow study while subjective evaluation is based on the restriction questionnaires studying factors affecting residents attitudes how to change before and after the restriction.The multivariate linear regression models are employed to evaluate the impact of restriction policies on motor vehicle traffic in a case study of Tianjin in this paper;on the other hand,the decision tree models are employed to evaluate the factors affecting the attitude towards the restriction policies.This paper studies the change of vehicle flows in different period of the day,when the vehicle restrictions applied in Tianjin.By selecting different independent variables and dependent variables,we study that limiting different number of tail numbers how to impact the vehicle flows on weekdays,vehicle restrictions how to impact vehicle flows on different roads and the change of vehicle flows on weekends.Our results show that the effects of restriction policies are lower than expected,and the effects are different in various road.In detail,the traffic flows in several main roads reduce to the biggest 16% due to the two-numbers restrictions on the last digit of license number;while the intersection traffic volume reduced to a maximum of 27.4% by even and odd-numbered license plates rules.Furthermore,the road traffic flows before the morning rush hour increase to the greatest 23.7% on weekdays when the two-numbers restriction policies are in-use,which means restriction policies make people set out in advance to circumvent the restriction policies.Interestingly,traffic flows on weekends increase 8%-22% after the two-numbers restriction policies implementation,which indicates that restriction policy implementation on weekdays makes the flexible travel demand shift to weekends,increasing travel needs and desires on weekends.Then,in this paper we use decision tree technique to evaluate the factors affecting the attitude towards the restriction policies: Residents understanding of restriction policies;the evaluations of others around residents on the restriction policy;evaluation about restriction policies in view of the impact on traffic in the future,and so on.