首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Capacity-constrained traffic forecasting model
Authors:Deo Chimba  Chang-Jen Lan
Institution:1. Department of Civil and Environmental Engineering , Tennessee State University , 3500 John Merritt Blvd, Nashville, TN, 37209, USA dchimba@tnstate.edu;3. Department of Civil and Environmental Engineering , Tennessee State University , 3500 John Merritt Blvd, Nashville, TN, 37209, USA
Abstract:Projecting future traffic is an important stage in any traffic and transportation planning study. Accurate traffic forecasting is vital for transportation planning, highway safety evaluation, traffic operations analysis, and geometric and pavement design among others. In view of its importance, this paper introduces a regression-based traffic forecasting methodology for a one dimensional capacity-constrained highway. Five different prediction functions are tested; the best was selected according to the accuracy of projections against historical traffic data. The three-parameter logistic function produced more accurate projections compared to other functions tested when highway capacity constraints were taken into consideration. The R 2 values at various test locations ranged from 88% to 98%, indicating good prediction capability. Using the Fisher's information matrix approach, the t-statistic test showed all parameters in the logistic function were highly statistically significant. To evaluate reliability of projections, predictive intervals were calculated at a 95% level of confidence. Predictions using the logistic function were also compared to those predicted using the compound growth rate and linear regression methods. The results show that the proposed methodology generates much more reasonable projections than current practices.
Keywords:traffic projection  capacity constraint  logistic function  traffic growth rate  confidence intervals
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号