<p>In this dissertation I present three chapters all related by their focus on issues of money and finance and the methodological treatment, the New Monetarist methodology, each considering different aspects of the international monetary-financial system. Williamson and Wright (2010) describe the New Monetarist methodology in detail, including enumerating several key principles, which put emphasis on microfoundations, especially of the frictions in the exchange process and financial intermediation arising from the environment, which are essential to analyses of macro and monetary economics. </p> <p><br></p> <p>The first chapter is entitled ``Optimal Monetary Policy and the Welfare Cost of Inflation of a Currency Union.'' It seeks to answer the question: How do retail trade frictions interact with immigration choices, and how does this interaction affect monetary policy in a currency union? This chapter studies the welfare cost of inflation and optimal monetary policy of a currency union between two countries using a search-theoretic framework with endogenous composition of buyers and sellers. The model includes three features of a currency union that are key to welfare and policy analysis: heterogeneous market structure, imperfect market integration, and immigration policy. The model yields optimal monetary policy that deviates from the Friedman rule, with the magnitude of inflation rate and welfare cost determined by different policy regimes. The Friedman rule is suboptimal, because a matching congestion externality in the labor market arises from the endogenous composition of buyers and sellers. Higher labor mobility reduces the cost of inflation by alleviating congestion, regardless of buyers' bargaining power. Market integration may also reduce congestion, lowering the cost of inflation, but only when sellers are relatively scarce.</p> <p><br></p> <p>The second chapter is entitled ``Liquidity, Collective Moral Hazard, and Government Bailouts''. It tries to answer the question: How does financial intermediaries risk taking respond to monetary/fiscal policy including bailout policy?</p> <p>This chapter develops a general equilibrium model of assets market integrating a theory of liquidity risk in a New Monetarist framework. Collective moral hazard arises from the interaction between banks' maturity transformation and government intervention. With the anticipation and implementation of government bailouts during a crisis, collective moral hazard creates current and deferred social costs. However,  under the ``correct" monetary policy, the costs are justified by the improvement of liquidity condition as a result of higher provision of public and private liquidity.</p> <p><br></p> <p>The third chapter is entitled  ``On Cross-Border Payments and the Industrial Organization of Correspondent Banking.''  It tries to answer the question: How does an understanding of the market structure of international banking affect recent suggestions for the improvement of cross-border payments?</p> <p>Despite advances in domestic payments arrangements in recent times, cross-border payments remain expensive and slow. This paper builds a model of bank-intermediated cross-border payments, identifying market power inherent to correspondent banking relationships as the key friction reducing efficiency. After developing a simple model of correspondent banking, we consider two policy experiments: the introduction by one country of an internationally held central bank digital currency (CBDC), and development of an internationally interoperable settlement system. Both policies can at least attenuate the inefficiencies in cross-border payments, but neither is automatically a complete solution nor are they without difficulties. For an international CBDC, we identify a political economy barrier: banks of the country potentially introducing the CBDC disproportionately suffer losses while benefits tend to accrue to foreign depositors, so a central bank concerned with its domestic banks' profitability may be unlikely to take such an action. Interoperability does not face the same barrier, as benefits accrue more symmetrically, but we argue that technical and other issues inherent to interoperability may be difficult to overcome.</p> <p><br></p>

Cette thèse comporte trois chapitres. Le premier chapitre décrit les moyens de paiement permettant le transfert de monnaie électronique (e-monnaie), les déterminants de leur adoption et leur usage dans le monde. Les deux chapitres suivants sont des articles qui analysent la concurrence entre la monnaie fiduciaire et l’e-monnaie à partir du modèle de Lagos-Wright (2005). Dans le premier article, à la différence des espèces, la détention d’e-monnaie est garantie contre le risque de perte ou de vol, et les marchands doivent investir pour recevoir l’e-monnaie. Du fait des complémentarités stratégiques entre les acheteurs et les vendeurs, il existe une multiplicité d’équilibres où seule une monnaie, ou les deux circulent. Nous analysons le bien-être et quantifions le modèle pour expliquer l’échec de l’e-monnaie en Europe et son succès en Asie et aux Etats-Unis. Dans le second article, les espèces concurrencent la monnaie mobile (M-monnaie). Les agents peuvent créer des partenariats et chaque transaction est réglée avec un seul moyen de paiement. Les agents sans partenaire utilisent les espèces, les autres utilisent l’M-monnaie. Les acheteurs avec un partenaire détiennent toujours de l’M-monnaie, seule ou en complément des espèces, alors que les acheteurs sans partenaire utilisent soit l’une, soit l’autre, soit les deux, soit aucune monnaie. Cependant, l’M-monnaie ne remplace les espèces que si le nombre de vendeurs traditionnels est très faible et l’inflation pas trop élevée. Ainsi, le partenariat est un mécanisme de coordination qui explique le succès des applications de paiement mobile proposées par des enseignes à leurs clients fidèles aux Etats-Unis. / This thesis has three chapters. The first chapter describes the means of payment allowingthe transfer of electronic money (e-money), the determinants of their adoption and their usein the world. The following two chapters are articles that analyze the competition between fiat money and e-money from the Lagos-Wright model (2005). In the first article, unlike cash, the holding of e-money is guaranteed against the risk of loss or theft, and merchants must invest to receive e-money. Due to strategic complementarities between buyers andsellers, there is a multiplicity of equilibria where only one money, or both, circulate. We analyze welfare and quantify the model to explain the failure of e-money in Europe and its success in Asia and in the United States. In the second article, cash competes with mobilemoney (M-money). Agents can create partnerships and each transaction is settled with one means of payment only. Agents without a partner use cash, the others use M-money.Buyers with a partner always hold M-money, alone or in addition to cash, while buyers without a partner use either one, or the other, or both, or no money. However, M-money replaces cash only if the number of traditional sellers is very low and inflation not too high.So, partnership is a coordination mechanism that explains the success of mobile payment applications offered by brands to their loyal customers in the United States.