Improving the accuracy of bubble date estimators under time-varying volatility

Eiji Kurozumi; Anton Skrobotov

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arXiv · 2306.02977

Improving the accuracy of bubble date estimators under time-varying volatility

Eiji Kurozumi·Anton Skrobotov

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Abstract

In this study, we consider a four-regime bubble model under the assumption of time-varying volatility and propose the algorithm of estimating the break dates with volatility correction: First, we estimate the emerging date of the explosive bubble, its collapsing date, and the recovering date to the normal market under assumption of homoskedasticity; second, we collect the residuals and then employ the WLS-based estimation of the bubble dates. We demonstrate by Monte Carlo simulations that the accuracy of the break dates estimators improve significantly by this two-step procedure in some cases compared to those based on the OLS method.

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Eiji Kurozumi, Anton Skrobotov. 2023-06-05. Improving the accuracy of bubble date estimators under time-varying volatility. https://arxiv.org/abs/2306.02977

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