Abstract Mixing up nondeterminism and probability: A preliminary
report
J.I. den Hartog and E.P. de Vink 

For a process language with both nondeterministic and probabilistic
choice, and a form of failure a transition system is given from which,
in a modular way, various operational models corresponding to various
interpretations of nondeterminism and probability can be obtained. The 
effect of failure of one component for the system as a whole is treated
differently in each interpretation. The same approach is followed for
an extension of the langauge with a parallel operator. The adopted
concurrency model is of a distributed nature and assumes that progress
is guaranteed if nonfailing components exist. To this end the notion of 
a take-over of a failing component is incorporated in the transition
system. It is shown that the modular way in which the transition
system can yield different semantical models applies to this setting
as well.