1 Search Results for "Ioannidis, Stavros D."

Document
Track A: Algorithms, Complexity and Games
DOI: 10.4230/LIPIcs.ICALP.2022.76
Strong Approximations and Irrationality in Financial Networks with Derivatives

Authors: Stavros D. Ioannidis, Bart de Keijzer, and Carmine Ventre

Published in: LIPIcs, Volume 229, 49th International Colloquium on Automata, Languages, and Programming (ICALP 2022)

Abstract
Financial networks model a set of financial institutions (firms) interconnected by obligations. Recent work has introduced to this model a class of obligations called credit default swaps, a certain kind of financial derivatives. The main computational challenge for such systems is known as the clearing problem, which is to determine which firms are in default and to compute their exposure to systemic risk, technically known as their recovery rates. It is known that the recovery rates form the set of fixed points of a simple function, and that these fixed points can be irrational. Furthermore, Schuldenzucker et al. (2016) have shown that finding a weakly (or "almost") approximate (rational) fixed point is PPAD-complete. We further study the clearing problem from the point of view of irrationality and approximation strength. Firstly, we observe that weakly approximate solutions may misrepresent the actual financial state of an institution. On this basis, we study the complexity of finding a strongly (or "near") approximate solution, and show FIXP-completeness. We then study the structural properties required for irrationality, and we give necessary conditions for irrational solutions to emerge: The presence of certain types of cycles in a financial network forces the recovery rates to take the form of roots of non-linear polynomials. In the absence of a large subclass of such cycles, we study the complexity of finding an exact fixed point, which we show to be a problem close to, albeit outside of, PPAD.
Cite as

Stavros D. Ioannidis, Bart de Keijzer, and Carmine Ventre. Strong Approximations and Irrationality in Financial Networks with Derivatives. In 49th International Colloquium on Automata, Languages, and Programming (ICALP 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 229, pp. 76:1-76:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)

Copy BibTex To Clipboard

@InProceedings{ioannidis_et_al:LIPIcs.ICALP.2022.76,
  author =	{Ioannidis, Stavros D. and de Keijzer, Bart and Ventre, Carmine},
  title =	{{Strong Approximations and Irrationality in Financial Networks with Derivatives}},
  booktitle =	{49th International Colloquium on Automata, Languages, and Programming (ICALP 2022)},
  pages =	{76:1--76:18},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-235-8},
  ISSN =	{1868-8969},
  year =	{2022},
  volume =	{229},
  editor =	{Boja\'{n}czyk, Miko{\l}aj and Merelli, Emanuela and Woodruff, David P.},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.ICALP.2022.76},
  URN =		{urn:nbn:de:0030-drops-164172},
  doi =		{10.4230/LIPIcs.ICALP.2022.76},
  annote =	{Keywords: FIXP, Financial Networks, Systemic Risk}
}
  • Refine by Author
  • 1 Ioannidis, Stavros D.
  • 1 Ventre, Carmine
  • 1 de Keijzer, Bart

  • Refine by Classification
  • 1 Theory of computation → Problems, reductions and completeness

  • Refine by Keyword
  • 1 FIXP
  • 1 Financial Networks
  • 1 Systemic Risk

  • Refine by Type
  • 1 document

  • Refine by Publication Year
  • 1 2022

Questions / Remarks / Feedback
X

Feedback for Dagstuhl Publishing


Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail
© 2023-2024 Schloss Dagstuhl – LZI GmbH Imprint Privacy Contact