[, ] () the amount by which measurements for members in a group vary from the average for the group标准差；标准偏差◆Our survey of 100 people showed that they spent an average of £52 on books per year, with a standard deviation of £12.我们对 100 个人所做的调查显示，他们每年花在买书上的钱平均为 52 英镑，标准偏差 12 英镑。➡mean , mode , range