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 Ni19Sm5
Value
Unit
Printed
Reading
Method (class, basis)
Composition
Scatter
Conversion
Effective
-36.5
kJ/mol-atom
0.05
3.9 (model_calculated, calibrated)
3.9
-34.5
kJ/mol-atom
0.05
3.9 (model_calculated, calibrated)
3.9
Sources
Z. Rahou, K. Mahdouk, Thermodynamic reassessment of the Sm–Ni binary system, Journal of Alloys and Compounds 664, 469-475 (2016). doi:10.1016/j.jallcom.2015.12.215