The Study Of Incorrectness On Newly-Built Highway Traffic Volume Prediction

Along with the sustainable development of economy and the rapid of the highway's construction, the highway was conceived as a sort of common and important carrier, it played an important role in the passenger and freight transportation. The traffic volume prediction not only was the base of the highway project feasibility research, but also was the main foundation of construction scale and standard. This article made a comparison between the prediction and the actual volume, through the analysis found the common predict incorrectness phenomenon.The phenomenon was emphasized on three steps. In the previous period, traffic forecast volume was higher than the actual; in the middle period, they were similar; in the long-term, forecast volume was lower than the actual. Based on this regularity, this article systematically researched the reason of the highway incorrectness prediction, and proposed the corresponding improvements and suggestions.At present stage, the research limited on the cause of the phenomenon of incorrectness, confine to select forecasting models, parameters or coefficient, and it ignored the total process of forecasting work. Based on highway traffic volume composed, form mechanism and influencing factors, this article expounds the relevant problems in newly-construction highway, sums up the total process of forecasting work, main content in earlier stage works, routine forecast methods, merit and shortcoming by oneself. By analyzing error between forecast volume and actual volune of two typical highway traffic, this article sums up objective law of newly-construction highway traffic volume foresting incorrectness, and builds the system of the reasons brought about incorrectness phenomenon, and looks for the reasons that lead incorrectness by arrangement of ideas and denomination in total system. The article submits improvement method and suggestion specifically for every concrete cause depended on the reason system. Especially it uses the growth curve method to forecast induced traffic volume, it found that the method can improve the prediction precision obviously through the examples'analysis. Finally, I used the Chengdu-Nanchong highway as an example to verify the improvement of the method of forecasting incorrectness, to analysis the reason Chengdu-Nanchong highway prediction incorrectness and proposed some corresponding solutions.