二个数值怎样表示?我国的习惯写法是一个值的测量结果写成L±R,其中L代表什么?R代表什么?这就是测量结果的不确定度问题。我们认为以代表X特征的平均值和三倍的标准差(即μ±3σ)来表征测量的不确定度,显得既实用又简便。其理由如下: 1.我国一般书藉在介绍测量误差与数据处理时,都写成L=L±σ_L。其中L是算术 How to express two values? Our habitual writing is a value of the measurement results written as L ± R, where L represents what? R represents what? This is the measurement uncertainty. We consider it practical and easy to characterize the measurement uncertainty by representing the mean of the X characteristics and the standard deviation of three times (ie, μ ± 3σ). The reasons are as follows: 1. China’s general book by introducing measurement error and data processing, are written as L = L ± σ_L. Where L is arithmetic