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Automatic Generation of Moment-Based Invariants for Prob-Solvable Loops

  • Ezio Bartocci
  • Laura KovácsEmail author
  • Miroslav Stankovič
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11781)

Abstract

One of the main challenges in the analysis of probabilistic programs is to compute invariant properties that summarise loop behaviours. Automation of invariant generation is still at its infancy and most of the times targets only expected values of the program variables, which is insufficient to recover the full probabilistic program behaviour. We present a method to automatically generate moment-based invariants of a subclass of probabilistic programs, called Prob-solvable loops, with polynomial assignments over random variables and parametrised distributions. We combine methods from symbolic summation and statistics to derive invariants as valid properties over higher-order moments, such as expected values or variances, of program variables. We successfully evaluated our work on several examples where full automation for computing higher-order moments and invariants over program variables was not yet possible.

Notes

Acknowledgements

We would like to thank Joost-Pieter Katoen for his constructive feedback on a preliminary version of the manuscript.

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Ezio Bartocci
    • 1
  • Laura Kovács
    • 1
    • 2
    Email author
  • Miroslav Stankovič
    • 1
  1. 1.TU WienViennaAustria
  2. 2.ChalmersGothenburgSweden

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