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arXiv · 2205.15808

Volatility Models for Stylized Facts of High-Frequency Financial Data

Donggyu Kim·Minseok Shin
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Abstract

This paper introduces novel volatility diffusion models to account for the stylized facts of high-frequency financial data such as volatility clustering, intra-day U-shape, and leverage effect. For example, the daily integrated volatility of the proposed volatility process has a realized GARCH structure with an asymmetric effect on log-returns. To further explain the heavy-tailedness of the financial data, we assume that the log-returns have a finite $2b$-th moment for $b \in (1,2]$. Then, we propose a Huber regression estimator which has an optimal convergence rate of $n^{(1-b)/b}$. We also discuss how to adjust bias coming from Huber loss and show its asymptotic properties.

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Donggyu Kim, Minseok Shin. 2022-05-31. Volatility Models for Stylized Facts of High-Frequency Financial Data. https://arxiv.org/abs/2205.15808

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