缺失数据下半参数回归模型的经验似然分析

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"薛留根的研究论文——'Empirical likelihood for semiparametric regression model with missing response data'" 这篇论文专注于探讨在存在缺失响应数据的情况下,如何运用下半参数回归模型的经验似然方法进行统计推断。薛留根,来自北京工业大学应用科学学院,通过一种纠偏技术来构建经验似然比,旨在解决缺失数据问题对模型估计的影响。 在统计学中,经验似然是一种非参数方法,它通过观察到的数据模拟似然函数,从而提供参数估计。对于含有缺失响应数据的半参数回归模型,传统的估计方法可能会受到偏差的影响。薛留根提出的方法旨在纠正这种偏差,同时避免在估计基础函数时出现过拟合(undersmoothing)的问题。通过定义一类特定的经验似然比函数,该方法能够在保持统计效率的同时,选择合适的带宽,这是数据驱动算法的一个关键部分。 论文的核心贡献在于,作者直接校准经验对数似然比,使得得到的比值在大样本情况下近似于卡方分布。这为参数估计提供了理论基础。此外,他们构造了一类参数的估计器,并得到了这些估计器的渐近分布。更重要的是,他们提供了渐近偏差和方差的一致估计器,这些工具可以用于构建参数的置信区间,这对于实际数据分析中的假设检验和预测具有重要意义。 这篇论文的成果不仅加深了我们对缺失数据下半参数回归模型的理解,还为处理类似问题提供了新的统计方法。在实际应用中,例如医学研究、社会科学或者经济学等领域,当数据不完整时,这一方法可能极大地提高模型估计的准确性和可靠性。

Please revise the paper:Accurate determination of bathymetric data in the shallow water zone over time and space is of increasing significance for navigation safety, monitoring of sea-level uplift, coastal areas management, and marine transportation. Satellite-derived bathymetry (SDB) is widely accepted as an effective alternative to conventional acoustics measurements over coastal areas with high spatial and temporal resolution combined with extensive repetitive coverage. Numerous empirical SDB approaches in previous works are unsuitable for precision bathymetry mapping in various scenarios, owing to the assumption of homogeneous bottom over the whole region, as well as the limitations of constructing global mapping relationships between water depth and blue-green reflectance takes no account of various confounding factors of radiance attenuation such as turbidity. To address the assumption failure of uniform bottom conditions and imperfect consideration of influence factors on the performance of the SDB model, this work proposes a bottom-type adaptive-based SDB approach (BA-SDB) to obtain accurate depth estimation over different sediments. The bottom type can be adaptively segmented by clustering based on bottom reflectance. For each sediment category, a PSO-LightGBM algorithm for depth derivation considering multiple influencing factors is driven to adaptively select the optimal influence factors and model parameters simultaneously. Water turbidity features beyond the traditional impact factors are incorporated in these regression models. Compared with log-ratio, multi-band and classical machine learning methods, the new approach produced the most accurate results with RMSE value is 0.85 m, in terms of different sediments and water depths combined with in-situ observations of airborne laser bathymetry and multi-beam echo sounder.

2023-02-18 上传