From the viewpoint of compatibility with ISO/IEC 15026, the most important issue is that SACM contain an "Uncertainty" characteristic or attribute, a key aspect of 15026-2, in order to facilitate use of SACM with ISO/IEC 15026 conformant assurance cases. These would be useful throughout SACM as attributes of assertions or claims (not relations).
Current usage means a need exists for several data type options not necessarily mutually exclusive.
Probability true: 0-1.00
Type I error: 0-1.00
Type 2 error: 0-1.00
Enumeration: None, low, medium, large, unknown
Standard deviation: real number
One might also want to include a data type with customizable meaning (values: 1-100) that would parallel the data type for “Strength” in present draft if this is retained.
This attribute element is associated with claims (assertions) and not with relations. Current SAEM draft defines characteristics such as “Strength,” and “Confidence” of evidence relations between an EvidenceItem (e.g. exhibit) and a DominAssertion. These relate to uncertainty but are associated with a relation and not with a DomainAssertion (claim). Note that the draft of SAEM states these are one-to-one relations unlike the many-to-one inferential relations in ARM.