Table 1. List of notations.

Notation	Description	Example
D	“Diagnosis” as the inference target node (random variable)	NA
di	state of random variable D	d1, primary lung cancer
Xj	imaging findings and clinical data as the other nodes (random variable)	shape, tumor marker
xjk	state of random variable Xj	x31, irregular
E	Evidence, as a set of xjk	{x11, x21}
p(di|E)	posterior probability of di when E is given to the inference model	NA
df	inference diagnosis with the highest posterior probability among p(di|E)	d1, primary lung cancer
Rc	reason candidate (a proper subset of E)	If x11 and x21 are given as E, then Rc can be {x11, x21}, {x11}, {x21}.
|Rc|	the number of elements of Rc	If Rc is {x11, x21}, then |Rc| is 2.
Rct	Rc with only one element	{x11}
I(Rc)	influence of Rc on the inference diagnosis df	NA
p(df)	prior probability of the inference diagnosis df	NA
pd(Rc)	difference between p(df|Rc) and p(df) for the inference diagnosis df	NA
V(S)	the performance metric of inference model S	NA
Vr(S)	explanation (reasoning) adequacy of inference model S	NA
Vi(S)	inference accuracy of inference model S	NA
Rg	Reference reasons (1–7 imaging findings and/or clinical data chosen by radiologists)	“shape is polygon,” “diameter is small and cavitation exists,” and “satellite lesion exists”
Rd	Reasons derived by the inference system	“shape is polygon” and “diameter is small and cavitation exists”

Abbreviation: NA, not available