Excessive functions, Appell polynomials and optimal stopping

The main topic of the thesis is optimal stopping. This is treated in two research articles. In the first article we introduce a new approach to optimal stopping of general strong Markov processes. The approach is based on the representation of excessive functions as expected suprema. We present a variety of examples, in particular, the Novikov-Shiryaev problem for Lévy processes. In the second article on optimal stopping we focus on differentiability of excessive functions of diffusions and apply these results to study the validity of the principle of smooth fit. As an example we discuss optimal stopping of sticky Brownian motion. The third research article offers a survey like discussion on Appell polynomials. The crucial role of Appell polynomials in optimal stopping of Lévy processes was noticed by Novikov and Shiryaev. They described the optimal rule in a large class of problems via these polynomials. We exploit the probabilistic approach to Appell polynomials and show that many classical results are obtained with ease in this framework. In the fourth article we derive a new relationship between the generalized Bernoulli polynomials and the generalized Euler polynomials.

Reflexivity in sovereign debt markets

Finanssi-instrumentin hinta määräytyy sen fundamenttitekijöiden perusteella, eikä päinvastoin. Tämä tutkimus osoittaa, että myös instrumentin hinta voi vaikuttaa fundamenttitekijöihin. Yhteys havainnollistetaan tapaustukimuksella Kreikan velkakriisistä. Hinnan ja fundamenttien välistä yhteyttä arvioidaan ja käänteisen kausaliteetin olemassaolo testataan. Tulokset tukevat ajatusta, jonka mukaan tarvitsemme dynaamisempia valuaatiomenetelmiä, jotka ottavat huomioon myös mahdolliset itseään vahvistavat hintakierteet.

A systematic mapping study on technical debt definition

The goal of this study was to explore and understand the definition of technical debt. Technical debt refers to situation in a software development, where shortcuts or workarounds are taken in technical decision. However, the original definition has been applied to other parts of software development and it is currently difficult to define technical debt. We used mapping study process as a research methodology to collect literature related to the research topic. We collected 159 papers that referred to original definition of technical debt, which were retrieved from scientific literature databases to conduct the search process. We retrieved 107 definitions that were split into keywords. The keyword map is one of the main results of this work. Apart from that, resulting synonyms and different types of technical debt were analyzed and added to the map as branches. Overall, 33 keywords or phrases, 6 synonyms and 17 types of technical debt were distinguished.

The debt crisis: a re-appraisal

The 1980s' debt crisis is a landmark in developing economies' growth and stabilization. According to the most quoted empirical articles, external shocks and vicissitudes gave rise to crisis just because of delays in stabilization policies, engendered by internal conflicts and institutional immaturity. I review some of these papers, and find out some problems - in the measurement of shocks and foreign indebtedness, namely - whose corrections lead to opposite results: external shocks and foreign indebtedness explain that crisis regardless of domestic policies. At the same time, the strong correlation of income distribution to terms of trade changes and foreign indebtedness suggest that inequality may have contributed differently to that crisis: either through an economic channel, or through a political channel based on delays in reforms.

The contagion effect of public debt on monetary policy: the Brazilian experience

This paper attempts to explain why the Brazilian inter-bank interest rate is so high compared with rates practiced by other emerging economies. The interplay between the markets for bank reserves and government securities feeds into the inter-bank rate the risk premium of the Brazilian public debt.

External debt in developing economies: assessment and policy issues

More than one decade after the external debt restructuring (the Brady Plan), a great amount of literature has been published concerning the balance sheet factors in developing countries. The staff of international multilateral institutions joined with reputable academics in this great controversy. The external debt problem of the developing countries is back and once more reflections on its cause and on policy recommendations are analytically distinct. Our main task is to reflect on the recent external debt dynamics and assess how this debt has evolved. Our findings indicate that the susceptibility of some developing countries to default is associated with global imbalance, that is, the way they borrow.

National exchange rate policies and international debt crises: how Brazil did not follow Argentina into a default in 2001-2002

This paper examines how exchange rate policies and IMF Stand-By Arrangements affect debt crises using econometrics and a comparison between Argentina and Brazil. It refines an existing diagram outlining crisis development to propose crisis prevention strategies. Flexible exchange rate policies reduce a country's probability of default by over 4%, but Stand-By Arrangements increase it by an inconsequential percentage. Unlike Argentina, Brazil avoided a default via a freely-floating exchange rate system, fiscal deficit reduction, and a cooperative and coordinated relationship with the IMF. The results provide policymakers from developing countries with lessons to manage their countries' default risks more effectively.

A gerência recente do endividamento público brasileiro

The recente Brazilian public management. We use two frameworks to analyze the recent Brazilian public debt management. The first one encompasses the Brazilian optimal public debt management analysis through the examination of the correlations among the main variables to which the public debt is indexed. The second seeks to address the consequences of recent Brazilian economic policies, such as international reserves accumulation through sterilized interventions by the Central Bank and excessive capitalization of federal financial institutions. Those policies have important, albeit often ignored, fiscal impacts, which became important to determine the current size, maturity and composition of the public debt stock.

« Pour le roy et l'eglise gallicane. Memoires sur lesquelz se pourront dresser les remonstrances qu'il seroit besoing faire au roy, nostre souverain seigneur, de la part de son procureur general, touchant l'excessive et intolérable substraction de deniers qui se tirent de ce royaume en court de Romme... » par JACQUES CAPPEL, avocat au parlement de Paris.

L'ouvrage commence (fol. 1) par : « Premierement sera presupposé que au roy, nostre souverain seigneur... » et finit (fol. 53) par : «... de messieurs du conseil privé du roy ». — Au fol. A v° sont peintes, à pleine page, les armes de France, avec accompagnement d'F couronnées. Reliure restaurée, portant sur les plats des fleurs de lis d'or, et dans la bordure de chaque plat des F, qui semblent avoir été peintes en argent.

Statement that Dr. Richard S. King became accountable for a Debt Owed to him by Dilly Coleman

Statement of Frederick Dilke of Port Robinson that Dr. Richard S. King became accountable for a debt owed to him by Dilly Coleman. The debt was assumed by Dr. Richard S. King, Sept. 24, 1850.

The Backing of Government Debt and the Price Level

This paper studies the interdependence between fiscal and monetary policies, and their joint role in the determination of the price level. The government is characterized by a long-run fiscal policy rule whereby a given fraction of the outstanding debt, say d, is backed by the present discounted value of current and future primary surpluses. The remaining debt is backed by seigniorage revenue. The parameter d characterizes the interdependence between fiscal and monetary authorities. It is shown that in a standard monetary economy, this policy rule implies that the price level depends not only on the money stock, but also on the proportion of debt that is backed with money. Empirical estimates of d are obtained for OECD countries using data on nominal consumption, monetary base, and debt. Results indicate that debt plays only a minor role in the determination of the price level in these economies. Estimates of d correlate well with institutional measures of central bank independence.

Valuing Sovereign Default Risk - A Pricing Formula and its Empirical Results for the Mexican External Debt.

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