Title
Optimization in curbing risk contagion among financial institutes.
Abstract
Financial institutions are interconnected by holding debt claims against each other. A default bank may cause its creditors to default, and the risk may be further propagated to up-stream institutes (risk contagion). Such interconnection is a key contributing factor to the past worldwide financial crisis. We show that a good mechanism of default liquidation may improve the total wealth of the financial system and therefore may curb the risk contagion. We formulate this problem as a nonlinear optimization problem with constraints and propose an optimal liquidation policy to minimize the system’s loss. We show that the problem resembles a Markov decision problem (MDP) and therefore we can apply the direct-comparison based optimization approach to solve this problem. Higher order directional derivatives and some optimality properties are obtained. Furthermore, we derive an iterative algorithm which combines both the policy iteration and the gradient based approach to find a local optimal policy, and under some conditions, a global optimal policy. Our work provides a new direction in curbing the risk contagion in financial networks; and it illustrates the advantages of the direct-comparison based approach, originated in the field of discrete event dynamic system, in nonlinear optimization problems.
Year
DOI
Venue
2018
10.1016/j.automatica.2018.04.036
Automatica
Keywords
Field
DocType
Direct-comparison based optimization,Discrete event systems,Perturbation analysis,Financial network,Markov decision problems,Risk contagion,Policy iteration,Sensitivity
Mathematical optimization,Iterative method,Financial crisis,Nonlinear programming,Discrete event dynamic system,Financial networks,Debt,Markov decision problem,Finance,Creditor,Mathematics
Journal
Volume
Issue
ISSN
94
1
0005-1098
Citations 
PageRank 
References 
0
0.34
6
Authors
4
Name
Order
Citations
PageRank
Xiang-Shen Ye100.68
Ruo-Bing Xue200.68
Jianjun Gao35111.33
Xi-Ren Cao4930123.58