The purpose of this study is to construct the ACD model for the block trading volume duration. The ACD model based on the block trading volume duration is referred to as Volume ACD (VACD) in this study. By integrating with GARCH-type models, the VACD based GARCH type models, which include VACD-GARCH, VACD-IGARCH and VACD-FIGARCH models, are set up. This study selects Chunghwa Telecom (CHT) Inc., offering the America Depository Receipt (ADR) in NYSE, to investigate the block trading volume duration in Taiwanese equity market. The empirical results indicate that the long memory in volume duration series increases dependence at level of volatility clustering by VACD (2,1)-FIGARCH (3,d,1) model. Moreover, the VACD (2,1)-IGARCH (1,1) exhibits relatively better performance of prediction on capturing block trading volume duration. This volatility model is more appropriate in this study to portray the change of the CHT Inc. prices and provides more information about the volatility process for investment strategy, which can be a reference indicator of financial asset pricing, hedging strategy and risk management.

Abstract
1. Introduction
2. Literature Review
3. Methodology
    3.1 GARCH-type Model
    3.2 ACD Model
    3.3. Testing Higher-Order VACD Model
    3.4. VACD-FIGARCH Model
4. Empirical Results and Analysis
    4.1. Data Description
    4.2. Empirical Results and Analysis
5. Conclusions
References

• Teng-Tsai TU(Graduate Institute of International Business, National Taipei University) Corresponding Author
• Chih-Wei LIAO(Department of Finance, Ming Chuan University)