摘要
该文建立了小波阈值消噪的统一阈值函数,推导了统一阈值函数的偏差、方差、风险的明确关系式。利 用这些公式研究了参数不同时(以u=1,2,∞为例)统一阈值函数估计的偏差、方差、风险与阈值以及小波系数的关 系,得到了小波统一阈值函数消噪估计的性能,对小波消噪在工程中应用有重要的理论指导意义。
In this paper, the uniform threshold function of waveshrink is build.Computationally efficient formulas for computing bias, variance and risk of uniform threshold function are derived. These formulas provide a new way of understanding how waveshrink works. On the basis of this, the relation of bias, variance and risk of uniform threshold function(u=1,2, ∞) with threshold value and wavelet coefficients are compared. These comparisons give the performance of waveshrink in finite sample situations.
出处
《电子与信息学报》
EI
CSCD
北大核心
2005年第4期536-539,共4页
Journal of Electronics & Information Technology
关键词
小波收缩
阈值函数
偏差估计
方差估计
风险估计
Wavelet shrinkage, Threshold function, Bias estimation, Variance estimation, Risk estimation
