We consider relative model comparison for the parametric coefficients of a semiparametric ergodic L\'{e}vy driven model observed at high-frequency. Our asymptotics is based on the fully explicit two-stage Gaussian quasi-likelihood function (GQLF) of the Euler-approximation type. For selections of the scale and drift coefficients, we propose explicit Gaussian quasi-AIC (GQAIC) and Gaussian quasi-BIC (GQBIC) statistics through the stepwise inference procedure. In particular, we show that the mixed-rates structure of the joint GQLF, which does not emerge for the case of diffusions, gives rise to the non-standard forms of the regularization terms in the selection of the scale coefficient, quantitatively clarifying the relation between estimation precision and sampling frequency. Numerical experiments are given to illustrate our theoretical findings.
翻译:我们考虑对在高频观察到的半参数ERgodic L\'{{e}vy 驱动模型的参数参数进行相对模型比较。 我们的无症状根据的是完全明确的两阶段高斯准类似功能(GQLF)的Euler-Approximation 类型。 对于比例和漂移系数的选择,我们建议通过渐进推论程序明确提供高西亚准AIC(GQAIC)和高西亚准BIC(GQBIC)统计数据。 特别是,我们表明,在扩散方面没有出现联合GQLF的混合率结构,导致在选择比额表系数时采用非标准形式的正规化条件,从数量上澄清估计精确度和取样频率之间的关系。我们用数字实验来说明我们的理论结论。