Non-Homogeneous Semi-Markov and Markov Renewal Processes and Change of Measure in Credit Risk

For a <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhomogeneous semi-Markov chain and <inline-formula><math display="inline"><semanti...

Full description

Bibliographic Details
Main Author: P.-C.G. Vassiliou
Format: Article
Language:English
Published: MDPI AG 2020-12-01
Series:Mathematics
Subjects:
Online Access:https://www.mdpi.com/2227-7390/9/1/55
_version_ 1827699061884452864
author P.-C.G. Vassiliou
author_facet P.-C.G. Vassiliou
author_sort P.-C.G. Vassiliou
collection DOAJ
description For a <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhomogeneous semi-Markov chain and <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhomogeneous Markov renewal processes, we study the change from real probability measure into a forward probability measure. We find the values of risky bonds using the forward probabilities that the bond will not default up to maturity time for both processes. It is established in the form of a theorem that the forward probability measure does not alter the semi Markov structure. In addition, foundation of a <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhohomogeneous Markov renewal process is done and a theorem is provided where it is proved that the Markov renewal process is maintained under the forward probability measure. We show that for an inhomogeneous semi-Markov there are martingales that characterize it. We show that the same is true for a Markov renewal processes. We discuss in depth the calibration of the <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhomogeneous semi-Markov chain model and propose an algorithm for it. We conclude with an application for risky bonds.
first_indexed 2024-03-10T13:41:46Z
format Article
id doaj.art-8622d72e98a04c4aa76377f2328cdbbf
institution Directory Open Access Journal
issn 2227-7390
language English
last_indexed 2024-03-10T13:41:46Z
publishDate 2020-12-01
publisher MDPI AG
record_format Article
series Mathematics
spelling doaj.art-8622d72e98a04c4aa76377f2328cdbbf2023-11-21T02:59:26ZengMDPI AGMathematics2227-73902020-12-01915510.3390/math9010055Non-Homogeneous Semi-Markov and Markov Renewal Processes and Change of Measure in Credit RiskP.-C.G. Vassiliou0Department of Statistical Sciences, University College London, Gower Street, London WC1E 6BT, UKFor a <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhomogeneous semi-Markov chain and <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhomogeneous Markov renewal processes, we study the change from real probability measure into a forward probability measure. We find the values of risky bonds using the forward probabilities that the bond will not default up to maturity time for both processes. It is established in the form of a theorem that the forward probability measure does not alter the semi Markov structure. In addition, foundation of a <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhohomogeneous Markov renewal process is done and a theorem is provided where it is proved that the Markov renewal process is maintained under the forward probability measure. We show that for an inhomogeneous semi-Markov there are martingales that characterize it. We show that the same is true for a Markov renewal processes. We discuss in depth the calibration of the <inline-formula><math display="inline"><semantics><mi mathvariant="script">G</mi></semantics></math></inline-formula>-inhomogeneous semi-Markov chain model and propose an algorithm for it. We conclude with an application for risky bonds.https://www.mdpi.com/2227-7390/9/1/55credit ratingnon-homogeneous semi-Markov chainsnon-homogeneous Markov renewal processeschange of measure
spellingShingle P.-C.G. Vassiliou
Non-Homogeneous Semi-Markov and Markov Renewal Processes and Change of Measure in Credit Risk
Mathematics
credit rating
non-homogeneous semi-Markov chains
non-homogeneous Markov renewal processes
change of measure
title Non-Homogeneous Semi-Markov and Markov Renewal Processes and Change of Measure in Credit Risk
title_full Non-Homogeneous Semi-Markov and Markov Renewal Processes and Change of Measure in Credit Risk
title_fullStr Non-Homogeneous Semi-Markov and Markov Renewal Processes and Change of Measure in Credit Risk
title_full_unstemmed Non-Homogeneous Semi-Markov and Markov Renewal Processes and Change of Measure in Credit Risk
title_short Non-Homogeneous Semi-Markov and Markov Renewal Processes and Change of Measure in Credit Risk
title_sort non homogeneous semi markov and markov renewal processes and change of measure in credit risk
topic credit rating
non-homogeneous semi-Markov chains
non-homogeneous Markov renewal processes
change of measure
url https://www.mdpi.com/2227-7390/9/1/55
work_keys_str_mv AT pcgvassiliou nonhomogeneoussemimarkovandmarkovrenewalprocessesandchangeofmeasureincreditrisk