Instruction manual

206 Chapter 9
Obtaining Statistical Data on Measurement Results
Overview of Functions for Statistical Analysis
Overview of Functions for Statistical Analysis
Agilent 4287A’s functions for statistical analysis allow you to store the required values of
measurement results (four measurement parameters, test signal voltage level monitor
value, test signal current level monitor value, DC resistance measurement value) in the
order of measurement internally in the unit. These functions also allow you to calculate and
display statistical data based on the stored data.
The parameter names and definitions of the statistical data that can be calculated and
displayed are shown in
Table 9-1.
Table 9-1 Statistical analysis parameters of 4287A
Parameter name Definition
Mean value (Mean)
(n = number of normal measurements, x
i
= normal
measurement number i)
Standard Deviation (SD)
(n = number of normal measurements, x
i
= normal
measurement number i)
3*SD/Mean
Minimum value (Min)
Smallest measured value among normal measurements
*1
Maximum value (Max) Largest measured value among normal measurements
Number of normal measurements
(Total = n)
Number of measurements performed normally
Number of Rdc limit deviations
(Rdc Fail)
Number of measurements where Rcd measurement value deviated from
the limit value
Number of overloads (Ovld) Number of measurements where overloaded occurred
Number of abnormal measurements
(Abnorm.)
Number of measurements where either Rdc limit deviation or overload
occurred
Total number of measurements (All) The total number of measurements (including abnormal measurements)
*1. Measurements where neither Rdc limit deviation nor overload occur.
x
i
i 1=
n

n
--------------
x
i
Mean–()
2
i 1=
n

n 1–
------------------------------------------
3 SD×
Mean
----------------