3A-TRE

3A-TRE evaluates traditionally logical expressions under the three assumptions. The open world assumption (OWA) states that the truth value of a statement that is not included in or inferred from the knowledge explicitly recorded in the system shall be considered unknown. The closed world assumption (CWA) is the assumption that any statement that is not known to be true is false. We distinguish yet another case in software testing. Frequently, there are test stubs which simulate the behaviors of the dependent test modules. In this case, the dependent test modules are always assumed to be true when their results are not available. We call this a stub assumption (SA).

3A-TRE example:
echo "CWA: (T and U)" | java -jar PTRE.jar
Result: F

3A-PTRE example: (P means possible results)
echo "OWA: (T,U and U,F)" | java -jar PTRE.jar
Result: U,F