Overnight GARCH-It\^o Volatility Models

Donggyu Kim; Minseok Shin; Yazhen Wang

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arXiv · 2102.13467

Overnight GARCH-It\^o Volatility Models

Donggyu Kim·Minseok Shin·Yazhen Wang

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Abstract

Various parametric volatility models for financial data have been developed to incorporate high-frequency realized volatilities and better capture market dynamics. However, because high-frequency trading data are not available during the close-to-open period, the volatility models often ignore volatility information over the close-to-open period and thus may suffer from loss of important information relevant to market dynamics. In this paper, to account for whole-day market dynamics, we propose an overnight volatility model based on It\^o diffusions to accommodate two different instantaneous volatility processes for the open-to-close and close-to-open periods. We develop a weighted least squares method to estimate model parameters for two different periods and investigate its asymptotic properties. We conduct a simulation study to check the finite sample performance of the proposed model and method. Finally, we apply the proposed approaches to real trading data.

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BibTeX RIS

Donggyu Kim, Minseok Shin, Yazhen Wang. 2021-02-24. Overnight GARCH-It\^o Volatility Models. https://arxiv.org/abs/2102.13467

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