2. Measurement Process Characterization
2.5. Uncertainty analysis
2.5.6. Uncertainty budgets and sensitivity coefficients

## Sensitivity coefficients for measurements on a check standard

From measurements on check standards If the temporal component of the measurement process is evaluated from measurements on a check standard and there are $$M$$ days ($$M = 1$$ is permissible) of measurements on the test item that are structured in the same manner as the measurements on the check standard, the standard deviation for the reported value is $$s_{reported \, value} = \frac{1}{\sqrt{M}} s_2$$ with degrees of freedom $$\nu_2 = K - 1$$ from the $$K$$ entries in the check standard database.
Standard deviation from check standard measurements The computation of the standard deviation from the check standard values and its relationship to components of instrument precision and day-to-day variability of the process are explained in the section on two-level nested designs using check standards.
Sensitivity coefficients The sensitivity coefficients are: $$a_1 = 0 ; \, a_2 = \sqrt{\frac{1}{M}}$$.