[Opt-Net] PACE 2023 Call for Participation

[Sebastian Berndt]

We are happy to announce the eighth iteration of PACE, the
Parameterized Algorithms and Computational Experiments Challenge. The
goals of PACE as well as official reports for past challenges can be
found on our website: https://pacechallenge.org/.

The challenge this year is a fascinating new width parameter:
twinwidth. It was introduced at FOCS 2020 by Bonnet, Kim, Thomassé,
and Watrigant and has seen an enormous amount of interest in the
research community resulting in papers at, e.g., SODA 2021, ICALP
2021, STOC 2022, SODA 2022, and ICALP 2022. Nevertheless, very little
is known about practically computing contraction sequences of small
width. We hope to remedy this situation in this year’s PACE challenge.


** Tracks
------------------------------------------------------------
We will have one track for exact algorithms and another for heuristic
algorithms.

**Exact:**
Your task is to find an optimal solution for each twinwidth
instance within 30 minutes. You will be ranked by the number of solved
instances.


**Heuristic:**
Your task is to find the best solution for each twinwidth instance
within 5 minutes. You will be ranked by the quality of the solution.



** Timeline
------------------------------------------------------------
- Already present on the webpage: Tiny test instances, input and
  output format descriptions, a verifier program, and more detailed
  ranking information.
- You can already run your solver on the tiny test instances on
  [optil.io](https://www.optil.io/optilion/problem/3204).
- January 2023: Public instances.
- March 2023: Submission via [optil.io](https://optil.io/) is open
  (for testing and an unofficial, auxiliary leaderboard).
- May 2023: The public leaderboard gets frozen.
- June 1st, 2023 (AoE): Submission deadline for solvers.
- June 15th, 2023 (AoE): Submission deadline for solver descriptions.
- July, 2023: Announcement of the results.
- 2023: Award ceremony at the International Symposium on Parameterized
  and Exact Computation (IPEC 2023).


** Program Committee
------------------------------------------------------------
- Max Bannach (co-chair) (Universität zu Lübeck)
- Sebastian Berndt (co-chair) (Universität zu Lübeck)

** Steering Committee
------------------------------------------------------------
* Holger Dell (Goethe University Frankfurt and IT University of Copenhagen)
* Johannes Fichte (Technische Universität Dresden)
* Markus Hecher (Technische Universität Wien)
* Bart M. P. Jansen (chair) (Eindhoven University of Technology)
* Łukasz Kowalik (University of Warsaw)
* André Nichterlein (Technical University of Berlin)
* Marcin Pilipczuk (University of Warsaw)
* Christian Schulz (Universität Heidelberg)
* Manuel Sorge (Technische Universität Wien)