arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0906.1698math.STstat.TH
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多尺度局部变点检测及其在风险价值中的应用

Multiscale local change point detection with applications to value-at-risk

Vladimir Spokoiny

摘要:

本文为非平稳时间序列的建模和预测提供了一种新的方法,并将其应用于金融数据的波动率建模。该方法是基于局部同质性的假设:对于每个时间点,存在一个历史区间的同质性,其中的波动率参数可以很好地近似为一个常数。建议的程序恢复这个时间间隔的数据,使用本地变点(LCP)分析。然后,波动率的估计可以简单地通过局部平均来获得。该方法仔细解决了使用所谓的"传播“条件选择过程的调谐参数的问题。主要结果声称一个新的“神谕”不等式的建模偏差,衡量当地常数近似的质量。这一结果产生的最佳估计率光滑和分段常数波动率函数。然后,新的程序被应用到一些数据集,并与标准的Gestival模型进行了比较。最后,我们讨论了新方法在风险价值问题中的应用。数值结果表明,新的方法是非常合理的性能。

英文摘要:

This paper offers a new approach to modeling and forecasting of nonstationary time series with applications to volatility modeling for financial data. The approach is based on the assumption of local homogeneity: for every time point, there exists a historical interval of homogeneity, in which the volatility parameter can be well approximated by a constant. The proposed procedure recovers this interval from the data using the local change point (LCP) analysis. Afterward, the estimate of the volatility can be simply obtained by local averaging. The approach carefully addresses the question of choosing the tuning parameters of the procedure using the so-called ``propagation'' condition. The main result claims a new ``oracle'' inequality in terms of the modeling bias which measures the quality of the local constant approximation. This result yields the optimal rate of estimation for smooth and piecewise constant volatility functions. Then, the new procedure is applied to some data sets and a comparison with a standard GARCH model is also provided. Finally, we discuss applications of the new method to the Value at Risk problem. The numerical results demonstrate a very reasonable performance of the new method.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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