HP 54710A User's Reference Manual page 121

Define Measure Menu
Statistics
Mean is calculated as:
∑
x
µ
= ; ( 1 ≤ n ≤ 65,534 ).
n
n
µ (n−1)+x
n−
1
µ
= ; n = 65,535.
n
n
µ = mean
n = count since last statistics reset
x = measurement result
Standard deviation is calculated as:
−1 ⁄
∑ ∑ 2
 
2 −( 2
n x x)
 
σ =
; (2 ≤ n ≤ 65,534).
n(n − 1)
 
( n−1) +x
= µ 2 2
µ
2 ; n = 65,535
n−1
n
n
⁄
−1
  2
2 2
−(µ
n[µ ]
n n)
σ =
; n = 65,535.
 
 n−1 
σ = standard deviation
n = count since last statistics reset
x = measurement result
min, max
Min (minimum) and max (maximum) are the absolute extremes of the
automatic measurement.
7–12