[1] Shi Guogang, Xiang Qiaojun, Guo Jianhua, Zhang Hongxin, et al. Effect of aggregation intervalon vehicular traffic flow heteroscedasticity [J]. Journal of Southeast University (English Edition), 2013, 29 (4): 445-449. [doi:10.3969/j.issn.1003-7985.2013.04.017]

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Effect of aggregation intervalon vehicular traffic flow heteroscedasticity()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

29

Issue:

2013 4

Page:

445-449

Research Field:

Traffic and Transportation Engineering

Publishing date:

2013-12-20

Info

Title:

Effect of aggregation intervalon vehicular traffic flow heteroscedasticity

Author(s):

Shi Guogang¹;  Xiang Qiaojun¹;  Guo Jianhua²;  Zhang Hongxin²

¹ School of Transportation, Southeast University, Nanjing 210096, China
²Intelligent Transportation System Research Center, Southeast University, Nanjing 210096, China

Keywords:

heteroscedasticity;  traffic flow;  autoregressive integrated moving average(ARIMA);  residual

PACS:

U491

DOI:

10.3969/j.issn.1003-7985.2013.04.017

Abstract:

The effect of the aggregation interval on vehicular traffic flow heteroscedasticity is investigated using real-world traffic flow data collected from the motorway system in the United Kingdom. 30 traffic flow series are generated using 30 aggregation intervals ranging from 1 to 30 min at 1 min increment, and autoregressive integrated moving average(ARIMA)models are constructed and applied in these series, generating 30 residual series. Through applying the portmanteau Q-test and the Lagrange multiplier(LM)test in the residual series from the ARIMA models, the heteroscedasticity in traffic flow series is investigated. Empirical results show that traffic flow is heteroscedastic across these selected aggregation intervals, and longer aggregation intervals tend to cancel out the noise in the traffic flow data and hence reduce the heteroscedasticity in traffic flow series. The above findings can be utilized in the development of reliable and robust traffic management and control systems.

References:

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Memo

Memo:

Biographies: Shi Guogang(1975—), male, graduate; Xiang Qiaojun(corresponding author), male, doctor, professor, xqj@seu.edu.cn.
Foundation items: The National Natural Science Foundation of China(No.71101025), the National Key Technology R&D Program of China during the 12th Five-Year Plan Period(No.2011BAK21B01), the Doctoral Programs Foundation of the Ministry of Education of China(No.20100092110037), the Fundamental Research Funds for the Central Universities.
Citation: Shi Guogang, Xiang Qiaojun, Guo Jianhua, et al. Effect of aggregation interval on vehicular traffic flow heteroscedasticity[J].Journal of Southeast University(English Edition), 2013, 29(4):445-449.[doi:10.3969/j.issn.1003-7985.2013.04.017]

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