We prove a tight upper bound on the variance of the priority sampling method (aka sequential Poisson sampling). Our proof is significantly shorter and simpler than the original proof given by Mario Szegedy at STOC 2006, which resolved a conjecture by Duffield, Lund, and Thorup.

翻译：我们给出了优先抽样方法（又称顺序泊松抽样）方差的一个紧的上界。我们的证明比Mario Szegedy在2006年STOC会议上给出的原始证明显著更短且更简单，该原始证明解决了Duffield、Lund和Thorup提出的一个猜想。