论文标题
关于自我激发跳跃系数的非参数推断
On the nonparametric inference of coefficients of self-exciting jump-diffusion
论文作者
论文摘要
在本文中,我们考虑了一个一维扩散过程,而霍克斯过程驱动的跳跃。我们对从长期的离散高频观察结果的波动率函数和跳跃函数的估计感兴趣,直到现在,这仍然是一个空旷的问题。首先,我们建议估计波动系数。 For that, we introduce a truncation function in our estimation procedure that allows us to take into account the jumps of the process and estimate the volatility function on a linear subspace of L2(A) where A is a compact interval of R. We obtain a bound for the empirical risk of the volatility estimator, ensuring its consistency, and then we study an adaptive estimator w.r.t.规律性。然后,我们定义一个估计器的波动率和跳跃系数之间的总和,并通过有条件地期望跳跃强度进行了修改。我们还建立了该总和非自适应估计量的经验风险,最终自适应函数规律性的收敛率以及最终自适应估算器的甲骨文不平等的界限。在本文中,我们提供了一种在某些应用中恢复跳跃功能的方法。我们进行了一项模拟研究,以测量估计器在实践中的准确性,并讨论从我们的估计过程中恢复跳跃函数的可能性。
In this paper, we consider a one-dimensional diffusion process with jumps driven by a Hawkes process. We are interested in the estimations of the volatility function and of the jump function from discrete high-frequency observations in a long time horizon which remained an open question until now. First, we propose to estimate the volatility coefficient. For that, we introduce a truncation function in our estimation procedure that allows us to take into account the jumps of the process and estimate the volatility function on a linear subspace of L2(A) where A is a compact interval of R. We obtain a bound for the empirical risk of the volatility estimator, ensuring its consistency, and then we study an adaptive estimator w.r.t. the regularity. Then, we define an estimator of a sum between the volatility and the jump coefficient modified with the conditional expectation of the intensity of the jumps. We also establish a bound for the empirical risk for the non-adaptive estimators of this sum, the convergence rate up to the regularity of the true function, and an oracle inequality for the final adaptive estimator.Finally, we give a methodology to recover the jump function in some applications. We conduct a simulation study to measure our estimators' accuracy in practice and discuss the possibility of recovering the jump function from our estimation procedure.