{"id":319,"date":"2026-04-15T13:46:36","date_gmt":"2026-04-15T11:46:36","guid":{"rendered":"https:\/\/members.loria.fr\/JGuichon\/?page_id=319"},"modified":"2026-04-15T16:05:26","modified_gmt":"2026-04-15T14:05:26","slug":"these-thesis","status":"publish","type":"page","link":"https:\/\/members.loria.fr\/JGuichon\/these-thesis\/","title":{"rendered":"Thesis\/Th\u00e8se"},"content":{"rendered":"
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English<\/span><\/p>\n

The Mutual Debt Reduction Problem in Business-to-Business Payment Networks<\/p>\n

PhD thesis in Computer Science \u2014 Universit\u00e9 de Lorraine, Inria, LORIA (UMR 7503)
\nSupervisors: Sylvain Contassot-Vivier & Nazim Fat\u00e8s<\/p>\n<\/td>\n

<\/td>\nFran\u00e7ais<\/span><\/p>\n

\u00c9tude du probl\u00e8me de la r\u00e9duction de dettes mutuelles dans les r\u00e9seaux de paiement entre entreprises<\/p>\n

Th\u00e8se de doctorat en informatique \u2014 Universit\u00e9 de Lorraine, Inria, LORIA (UMR 7503)
\nDirecteurs : Sylvain Contassot-Vivier & Nazim Fat\u00e8s<\/p>\n<\/td>\n<\/tr>\n

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Context and motivation<\/p>\n

In modern economies, trade credit between firms is the primary source of short-term financing, exceeding total bank credit in volume. Each outstanding invoice contributes to a continuously evolving network of financial obligations. When liquidity tightens, stress propagates in cascades along supply chains, a phenomenon well-documented in major financial crises (2008, COVID-19) but present on an endemic basis.<\/p>\n

Multilateral integral netting appears as a promising mechanism to reduce these liquidity needs, yet its effective implementation in real-world B2B networks raises open algorithmic, structural, and economic challenges.<\/p>\n<\/td>\n

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Contexte et motivation<\/p>\n

Dans les \u00e9conomies contemporaines, le cr\u00e9dit inter-entreprises constitue la principale source de financement \u00e0 court terme, repr\u00e9sentant un volume sup\u00e9rieur \u00e0 l’ensemble des cr\u00e9dits bancaires. Chaque facture \u00e9mise forme un r\u00e9seau d’obligations financi\u00e8res en perp\u00e9tuelle \u00e9volution. Lorsque la liquidit\u00e9 se rar\u00e9fie, les tensions se propagent en cascade le long des cha\u00eenes de fournisseurs, un ph\u00e9nom\u00e8ne document\u00e9 lors des grandes crises financi\u00e8res (2008, COVID-19) mais pr\u00e9sent de fa\u00e7on end\u00e9mique.<\/p>\n

La compensation multilat\u00e9rale int\u00e9grale appara\u00eet comme un m\u00e9canisme susceptible de r\u00e9duire ces besoins de liquidit\u00e9, mais sa mise en \u0153uvre effective dans les r\u00e9seaux B2B r\u00e9els soul\u00e8ve des d\u00e9fis algorithmiques, structurels et \u00e9conomiques encore ouverts.<\/p>\n<\/td>\n<\/tr>\n

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Main contributions<\/p>\n<\/td>\n

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Contributions principales<\/p>\n<\/td>\n<\/tr>\n

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Structural characterisation of B2B debt networks<\/strong>
\nTopological analysis of a large-scale real dataset of over 22 million invoices (InfoCert, Italy, 2019): power-law degree distributions, community structures, and structural asymmetries specific to economic networks. Published at Complex Networks 2023.<\/span><\/div>\n<\/td>\n
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Caract\u00e9risation structurelle des r\u00e9seaux de dettes B2B<\/strong>
\nAnalyse topologique d’un jeu de donn\u00e9es r\u00e9el de plus de 22 millions de factures (InfoCert, Italie, 2019) : distributions de degr\u00e9s en loi de puissance, structures communautaires, asym\u00e9tries propres aux r\u00e9seaux \u00e9conomiques. Publi\u00e9 \u00e0 Complex Networks 2023.<\/span><\/div>\n<\/td>\n<\/tr>\n
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Integral netting heuristic on static graphs<\/strong>
\nFormalisation of the integral multilateral netting problem (NP-hard) and design of an optimisation heuristic guided by a propagation potential index. Introduced metrics include: financing amplification factor, invoice inclusion rate, and netting gain. Presented at FRCCS 2025. Extended paper under review at Advances in Complex Systems<\/em>.<\/span><\/div>\n<\/td>\n
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Heuristique de compensation int\u00e9grale sur graphe statique<\/strong>
\nFormalisation du probl\u00e8me de mutualisation int\u00e9grale (NP-difficile) et conception d’une heuristique d’optimisation guid\u00e9e par un indice de potentiel de propagation. M\u00e9triques introduites : facteur d’amplification du financement, taux d’inclusion des factures, gain de compensation. Pr\u00e9sent\u00e9 \u00e0 FRCCS 2025. Article d\u00e9taill\u00e9 en r\u00e9vision dans Advances in Complex Systems<\/em>.<\/span><\/div>\n<\/td>\n<\/tr>\n
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Scalability : divide-and-conquer approach<\/strong>
\nGraph decomposition strategies (node-centered and edge-centered) enabling the processing of graphs with several million edges within reasonable computation times, while preserving comparable netting efficiency. Presented at CSS 2025.<\/span><\/div>\n<\/td>\n
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Passage \u00e0 l’\u00e9chelle : approche divide-and-conquer<\/strong>
\nStrat\u00e9gies de d\u00e9composition du graphe (centr\u00e9e n\u0153uds et centr\u00e9e arcs) permettant de traiter des graphes de plusieurs millions d’arcs avec des temps de calcul raisonnables, tout en conservant une efficacit\u00e9 de compensation comparable. Pr\u00e9sent\u00e9 \u00e0 CSS 2025.<\/span><\/div>\n<\/td>\n<\/tr>\n
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Financing constraints and dynamic temporal framework<\/strong>
\nExtension of the static model to a dynamic setting with successive netting sessions, continuous invoice arrival, and progressive repayment. Simulations on InfoCert data show convergence of the funder’s capital towards a stationary regime, supporting the long-term sustainability of the mechanism.<\/span><\/div>\n<\/td>\n
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Contraintes de financement et cadre temporel dynamique<\/strong>
\nExtension du mod\u00e8le statique \u00e0 un cadre dynamique avec sessions successives, arriv\u00e9e continue de factures et remboursement progressif. Les simulations montrent la convergence du capital du financeur vers un r\u00e9gime stationnaire, sugg\u00e9rant la soutenabilit\u00e9 du m\u00e9canisme \u00e0 long terme.<\/span><\/div>\n<\/td>\n<\/tr>\n
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Economic implications<\/strong>
\nAnalysis of how netting benefits are distributed across firms according to their structural position, and of funder exposure. The high granularity of the financing portfolio reduces idiosyncratic risk.<\/span><\/div>\n<\/td>\n
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Implications \u00e9conomiques<\/strong>
\nAnalyse de la distribution des b\u00e9n\u00e9fices de la compensation selon la position structurelle des entreprises, et de l’exposition du financeur. La forte granularit\u00e9 du portefeuille de financements r\u00e9duit le risque idiosyncratique.<\/span><\/div>\n<\/td>\n<\/tr>\n
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Follow-up : Inria Startup Studio<\/strong>
\nThis thesis work is continuing within the Inria Startup Studio programme, with the goal of exploring the technical, economic, and institutional conditions for an operational large-scale deployment.<\/span><\/div>\n<\/td>\n
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Suite du projet : Inria Startup Studio<\/strong>
\nLes travaux de cette th\u00e8se se prolongent dans le cadre du programme Inria Startup Studio, avec pour objectif d’explorer les conditions techniques, \u00e9conomiques et institutionnelles n\u00e9cessaires \u00e0 un d\u00e9ploiement op\u00e9rationnel \u00e0 grande \u00e9chelle.<\/span><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
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Related publications \/ Publications associ\u00e9es<\/strong>
\n Full list of papers, conference proceedings and posters related to this thesis. — Liste compl\u00e8te des articles, conf\u00e9rences et posters li\u00e9s \u00e0 cette th\u00e8se<\/span><\/div>\n

Voir les publications \u2192<\/a>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

English The Mutual Debt Reduction Problem in Business-to-Business Payment Networks PhD thesis in Computer Science \u2014 Universit\u00e9 de Lorraine, Inria, LORIA (UMR 7503) Supervisors: Sylvain Contassot-Vivier & Nazim Fat\u00e8s Fran\u00e7ais \u00c9tude du probl\u00e8me de la r\u00e9duction de dettes mutuelles dans les r\u00e9seaux de paiement entre entreprises Th\u00e8se de doctorat en informatique \u2014 Universit\u00e9 de Lorraine, […]<\/p>\n","protected":false},"author":232,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-319","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/members.loria.fr\/JGuichon\/wp-json\/wp\/v2\/pages\/319","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/members.loria.fr\/JGuichon\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/members.loria.fr\/JGuichon\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/members.loria.fr\/JGuichon\/wp-json\/wp\/v2\/users\/232"}],"replies":[{"embeddable":true,"href":"https:\/\/members.loria.fr\/JGuichon\/wp-json\/wp\/v2\/comments?post=319"}],"version-history":[{"count":21,"href":"https:\/\/members.loria.fr\/JGuichon\/wp-json\/wp\/v2\/pages\/319\/revisions"}],"predecessor-version":[{"id":343,"href":"https:\/\/members.loria.fr\/JGuichon\/wp-json\/wp\/v2\/pages\/319\/revisions\/343"}],"wp:attachment":[{"href":"https:\/\/members.loria.fr\/JGuichon\/wp-json\/wp\/v2\/media?parent=319"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}