The 4th International Seminar of Committee of Infrastructure Planning and Management, JSCE in FY2012
2012年度土木計画学研究委員会 第4回国際セミナー（通算 第62回国際セミナー）

・講演タイトル：Temporal Aggregation in Traffic Forecasting: Implications for Statistical Characteristics and Model Choice
（交通需要予測における時間的な集計：統計的な特性とモデルの選択への示唆）

・講演概要：
Temporal Aggregation in Traffic Forecasting: Implications for Statistical Characteristics and Model Choice Time series techniques are useful for analyzing transportation data, uncovering past trends and providing projections. Such analyses are sensitive to the temporal aggregation of the data, an issue that has been widely ignored in the transportation literature. In traffic engineering, aggregation usually equals to the average of a variable across large regular time intervals, such as 15 minutes, hours, days, months and so on. We investigate the effects of temporal aggregation on time series of traffic volume and occupancy in urban signalized arterials. Results indicate that aggregation eliminates long memory characteristics and variance heterogeneity; this leads to smoothing traffic variation and creating a time series structure that has reduced sensitivity to changes in traffic. Moreover, aggregation was found to directly affect volatility as captured by the parameters of the Generalized Auto-Regressive Conditionally Heteroskedastic (GARCH) models.

・講演者：Matthew G. Karlaftis, Associate Professor of the National
Technical University of Athens（国立アテネ工科大学准教授）

・日時：2012年7月10日（火）16:00-17:00

・場所：東京大学工学部1号館2階社会基盤学科セミナーB室
（工学部1号館へのアクセスは，http://www.u-tokyo.ac.jp/campusmap/cam01_04_02_j.htmlをご覧ください．）

・言語：英語

・参加手続き：無料です．事前に以下の連絡先まで，連絡をお願いします．ただし，当日の突然参加も大歓迎です．

・連絡・問い合わせ先：加藤浩徳（kato@civil.t.u-tokyo.ac.jp）