Dear all,
You are cordially invited to the Bachelor's thesis talk of Leander Besting on 28.04.2025 at 14:00h in Seminar room of I1. The title and the abstract of the talk are as follows:
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Title: /Claims Trading for Least Clearing States in Financial Networks
/Abstract:/
/The notion of a claims trade, within the financial network model of Eisenberg and Noe [1], was introduced in a recent paper by Hoefer, Ventre and Wilhelmi [2]. It studies how the legal framework of Chapter 11 bankruptcy, particularly a creditor’s ability to sell claims, can be used to stabilize a financial network from within, avoiding external, especially governmental, involvement. In this thesis we consider the novel approach of judging a claims trade’s effect based on the least clearing state and not the greatest, which is typically considered for Eisenberg-Noe networks. The least clearing state represents the outcome of a decentralized clearing process, rather than a centralized one.
To this end, we introduce a new clearing algorithm. Unlike most previous algorithms, ours computes the least clearing state.
Additionally it works on all common types of payment strategies and even possible combinations of these, where previous
algorithms only worked for one specific type of strategy. Afterwards, we look at the previous methods for finding optimal claims trades. We give pathological examples, showing that they cannot be adapted to the least clearing state, and then discuss intuitions for why they behave differently in this scenario. This is followed by a new algorithm for finding optimal claims trades, w.r.t. the least clearing state. Our claims trading algorithm works on the same strategy profiles as our clearing algorithm. In particular, this covers all payment strategies for which claims trading algorithms are known w.r.t. the greatest clearing state.
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Best regards,
Sukanya
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Sukanya Pandey
Postdoctoral Researcher
Algorithms and Complexity Chair
RWTH Aachen
sukanyapandey.com
Dear all,
the DFG Research Unit ADYN invites you to their next online seminar
session on Zoom:
*Monday, April 7th, 17:00 CEST*.
Link:
https://rwth.zoom-x.de/j/68837156442?pwd=H4OW7bUYYAMXSPiqvxXuEMuTTmk7VY.1
Meeting-ID: 688 3715 6442
Kenncode: 593098
The following talks will be given:
(1) "Constraint Satisfaction Problems with Advice" by Suprovat Ghoshal
(Indiana University)
(2) "A Combinatorial Approach to Chernoff Bounds" by William Kuszmaul
(Carnegie Mellon University)
Abstracts:
(1) We initiate the study of algorithms for Constraint Satisfaction
Problems (CSPs) with ML oracle advice. We introduce two models of advice
and then design approximation algorithms for several fundamental CSPs,
such as Max Cut, Max 2-Lin, and Max 3-Lin in these models. In
particular, we show the following.
1. For Max-Cut and Max 2-Lin, we design an algorithm that yields
near-optimal solutions when the average degree is larger than a
threshold degree, which only depends on the amount of advice and is
independent of the instance size. We also give an algorithm for nearly
satisfiable Max 3-Lin instances with quantitatively similar guarantees.
2. Further, we provide impossibility results for algorithms in these
models. In particular, under standard complexity assumptions, we show
that Max 3-Lin is still $1/2 + \eta$ hard to approximate given access to
advice, when there are no assumptions on the instance degree
distribution. Additionally, we also show that Max 4-Lin is $1/2 + \eta$
hard to approximate even when the average degree of the instance is
linear in the number of variables.
This is joint work with Konstantin Makarychev and Yury Makarychev.
(2) -
For more information on ADYN and the seminar series, visit our website
using the link https://adyn.informatik.rwth-aachen.de/ .
Best,
Tim
