GB/T 11718-202X
Appendix A
(normative appendix)
The calculation of the 5% and 95% denominations
A.1 Overview
This appendix provides for the calculation of the 5% and 95% denominations.
A.2 symbol
The common symbols used in this appendix are as follows:
m – the number of specimens taken by each model in the vertical and horizontal directions
X5% – the next 5% of the sample
S – Standard deviation calculated from test or measurement values
Sw, j — the standard deviation X95% of the sample for the sample — the upper 95% bit value of the sample
Xij- Test or measurement
jx – the arithmetic average of m individual test values or measurementsobtained from a single model j
tm – At the α of the significance level, the m-block specimen is normally distributed on one side of the t-value
A.3 calculation
A.3.1 Average per model (board average)
The arithmetic mean of the m test values in the model j is calculated by formula (A.1):
The standard deviation of the standard deviation model in the formula.
A.3.2 board j in the m test value of the standard deviation is calculated by formula (A.2):
A.3.3 The 5% bit value of the normal distribution of the performance of the model and the 5% bit value and the 95% bit of the normal distribution of the performance of each model test performance are calculated by formula (A.3) and formula (A.4), respectively:）
GB/T 11718-202X
Note: In the formula CV is the coefficient of variation,j, x/CVjwS, if the coefficient of variation CV is less than 0.08, then the CV takes 0.08 for the formula (A.. 3) And type (A. 4）
A.4 Calculated
Tm is the normaldistribution t value on one side of the m-block specimen at the α of the significance level, and 89.1m-t when m-8, and when m-1280.1m=t.