BSA調查（BSA Survey）被視為民調產業的「黃金標準」，因為它歷史悠久，且使用隨機機率抽樣——意味英國所有人都有相同機會被抽中。
Source: Computational Materials Science, Volume 267
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"At that point my kids were a bit older… and, you know, that almost enables you to push harder. Like… 'I bet if I get up at three this morning, I can surprise [a perpetrator] online.'
The pruned nodes (in red) represent entire regions of space that the algorithm never examines. The points inside those regions are never checked. Compare the "Nodes Visited" count to the total number of points. The quadtree is doing far less work than a brute-force scan.