Difference estimation 差额估计法 ; 差额估计抽样 ; 差异测定法

time difference estimation 时间差估计

Estimation of Difference Models 差分模型的估计

estimation of difference of means 平均值差估计

ratio and difference estimation sampling 比率差异推算抽样法

Difference-in-Differences Estimation 采用双重差分估计策略

phase difference estimation 相位差估算

gray scale difference estimation 灰度差估计

estimation of frequency difference 频差估计