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 NbZn15
Value
Unit
Printed
Reading
Method (class, basis)
Composition
Scatter
Conversion
Effective
-3.636
kJ/mol (basis unstated)
5.000e-4
3.9 (model_calculated, calibrated)
3.9
-3.637
kJ/mol (basis unstated)
5.000e-4
8.395 (dft, calibrated)
8.395
Sources
Zhaohui Long, Jin Gong, Jing Ding, Chihua Tang, Zhi Li, Fucheng Yin, Thermodynamic Assessment of Zn-Fe-Nb Ternary System, J. Phase Equilib. Diffus. 37, 293-300 (2016). doi:10.1007/s11669-016-0457-z