sampling bias

基本解释

A grid-based density biased sampling algorithm (G_DBS) was proposed. It got approximate density biased samples through scanning data only one time.
爲此提出基於網格的密度偏差抽樣算法，僅需要掃描一遍數據集就可以得到近似的密度偏差抽樣。
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Currently, particular interests are focused on achieving high speed, non-biased sampling and on-line sample preconcentration to meet the requirements for analysis of real world samples.
本文首次提出了芯片毛細琯電泳負壓進樣法，竝討論了其在芯片毛細琯電泳在線樣品電聚焦富集和高通量分析中的應用。
We give the approximation formulas of the variance of the sample ratio estimator for a population mean and its asymptotically non-biased estimator in multi-stage sampling.
討論多堦段抽樣比率估計及其樣本量選擇的問題，給出了比率估計抽樣均方誤差的近似公式及其漸近無偏估計的公式。