This book constitutes the proceedings of the 19th International Conference on Quantitative Evaluation Systems, QEST 2022, held in Warsaw, Poland, in September 2022.The 19 full papers presented together with 1 keynote paper were carefully reviewed and selected from 44 submissions. The papers are organized in the following topics: program analysis; parameter synthesis; markovian agents and population models; dynamical systems; tools; applications and automata theory; and applications.

This book constitutes the refereed proceedings of the 13th European Workshop on Computer Performance Engineering, EPEW 2016, held in Chios, Greece, in October 2016. The 14 papers presented together with 2 invited talks in this volume were carefully reviewed and selected from 25 submissions. The papers presented at the workshop reflect the diversity of modern performance engineering, with topics ranging from the analysis of queueing networks and stochastic processes, to performance analysis of computer systems and networks, and even modeling of human behavior.