Estimating ranks, quantiles, and distributions over streaming data is a central task in data analysis and monitoring. Given a stream of n items from a data universe equipped with a total order, the task is to compute a sketch (data structure) of size polylogarithmic in n. Given the sketch and a query item y, one should be able to approximate its rank in the stream, i.e., the number of stream elements smaller than or equal to y.

中文翻译：

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相对误差流分位数

估计流数据的等级、分位数和分布是数据分析和监控的核心任务。给定来自配备了总顺序的数据宇宙的 n 项流，任务是计算大小为 n 的多对数的草图（数据结构）。给定草图和查询项 y，应该能够近似其在流中的排名，即小于或等于 y 的流元素的数量。