# Median Define 统计学上，中位数（Median），又称中央值、中值，是一个样本、种群或概率分布中之一个数值，其可将数值集合划分为数量相等的上下两部分。对于有限的数集，可以通过把所有观察值高低排序后找出正中间的一个作为中位数。如果观察值有偶数个，则中位数不唯一，通常取最中间的两个数值的平均数作为中位数。 一个数集中最多有一半的数值小于中位数，也最多有一半的数值大于中位数。如果大于和小于中位数的数值个数均少于一半，那么数集中必有若干值等同于中位数。 # Data Set 123456789101112create table movie_ratings ( rating...

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