Components kept separate, in the value's unit (literature SCHEMA.md, UNCERTAINTY_CALIBRATION.md): effective = max(sqrt(max(printed, reading, method)^2 + composition^2 + conversion^2), scatter). The method floor is the robust between-study scatter of the method class in ORCHID (calibrated) or a documented prior; printed values and printed uncertainties are unchanged.
Uncertainty budget of the literature values of Zr2N
Value
Unit
Printed
Reading
Method (class, basis)
Composition
Scatter
Conversion
Effective
-219.829
kJ/mol-atom
3.333e-4
9.966 (dft, calibrated)
9.966
-130.064
kJ/mol-atom
3.333e-4
9.966 (dft, calibrated)
9.966
Sources
Xiaoyan Ma, Changrong Li, Kewu Bai, Ping Wu, Weijing Zhang, Thermodynamic assessment of the Zr–N system, Journal of Alloys and Compounds 373, 194-201 (2004). doi:10.1016/j.jallcom.2003.10.051