Issue No.02 - March/April (2009 vol.35)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TSE.2008.106
We extend the classical system relations of trace inclusion, trace equivalence, simulation, and bisimulation to a quantitative setting in which propositions are interpreted not as boolean values, but as elements of arbitrary metric spaces. Trace inclusion and equivalence give rise to asymmetrical and symmetrical linear distances, while simulation and bisimulation give rise to asymmetrical and symmetrical branching distances. We study the relationships among these distances and we provide a full logical characterization of the distances in terms of quantitative versions of LTL and mu-calculus. We show that, while trace inclusion (respectively, equivalence) coincides with simulation (respectively, bisimulation) for deterministic boolean transition systems, linear and branching distances do not coincide for deterministic metric transition systems. Finally, we provide algorithms for computing the distances over finite systems, together with a matching lower complexity bound.
Logic, Extraterrestrial measurements, Cost accounting, Computational modeling, Reasoning about programs, Formal languages, Software tools, Digital audio players, Clocks, Automata, Modal logic, Logics of programs, Specification techniques
"Linear and Branching System Metrics", IEEE Transactions on Software Engineering, vol.35, no. 2, pp. 1, March/April 2009, doi:10.1109/TSE.2008.106