Oscilloscopes User's Guide

Making Measurements 5
6000 Series Oscilloscope User’s Guide 253
The mean is calculated as follows:
where:
x
= the mean.
N = the number of measurements taken.
x
i
= the i
th
measurement result.
The standard deviation is calculated as follows:
where:
σ = the standard deviation.
N = the number of measurements taken.
x
i
= the i
th
measurement result.
x
= the mean.
-2s
mean
-1s 1s
2s
68.3%
-3s
95.4%
99.7%
03s
x
x
i
i 1=
N
∑
N
--------------=
σ
x
i
x–()
2
i 1=
N
∑
N 1–
------------------------------=