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arXiv · 1011.2635

Is Brownian motion necessary to model high-frequency data?

Yacine Aït-Sahalia·Jean Jacod
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Abstract

This paper considers the problem of testing for the presence of a continuous part in a semimartingale sampled at high frequency. We provide two tests, one where the null hypothesis is that a continuous component is present, the other where the continuous component is absent, and the model is then driven by a pure jump process. When applied to high-frequency individual stock data, both tests point toward the need to include a continuous component in the model.

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Yacine Aït-Sahalia, Jean Jacod. 2010-11-11. Is Brownian motion necessary to model high-frequency data?. https://doi.org/10.1214/09-aos749

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