  This paper introduces a new technique for dynamic verification of
component-based real-time systems based on statistical inference. Verifying
such systems requires checking two types of properties: functional and
real-time. For functional properties, a standard approach for ensuring
correctness is Design by Contract: annotating programs with executable pre- and
postconditions. We extend contracts for specifying real-time properties. In the
industry, components are often bought from vendors and meant to be used
off-the-shelf which makes it very difficult to determine their execution times
and express related properties. We present a solution to this problem by using
statistical inference for estimating the properties. The contract framework
allows application developers to express contracts like "the execution time of
component $X$ lies within $\gamma$ standard deviations from the mean execution
time". Experiments based on industrial case studies show that this framework
can be smoothly integrated into existing control applications, thereby
increasing their reliability while having an acceptable execution time overhead
(less than 10%).
