Scale-Freeness of SPA Models with Weighted Immediate Actions

  • Johann Schuster
  • Markus Siegle
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7587)


Whenever a process algebra uses weights for specifying probabilities, it is desirable that the rescaling of a submodel’s weights by a constant factor does not affect the resulting overall model. A classical weighted approach, which is independent of rescaling weights in submodels, is the WSCCS approach by Tofts. The stochastic process algebra CASPA also uses weights, but the results are in general not independent of rescaling the submodels’ weights. This paper develops necessary and sufficient criteria for CASPA models to be independent of rescalings. In addition to the general notion of scale-freeness, weaker notions that do not regard vanishing states or target on certain measures are also considered.


stochastic process algebra scale-free CASPA nondeterminism 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Johann Schuster
    • 1
  • Markus Siegle
    • 1
  1. 1.University of the Federal Armed Forces MunichGermany

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