In recent times some economists and politicians in the context of financial crisis dusted off again the idea of introducing the so-called Tobin tax, or financial transaction tax (FTT), respectively. This thesis briefly reviews the existing literature on FTT. Two case studies of Sweden and Great Britain show in some respects two different experiences with FTT. The theses analyzes in detail the economic implications of the European Commission proposed FTT from the perspective of economic theory and economic policy. Partial conclusions of the thesis reveal some drawbacks and pitfalls of FTT. While the benefits of FTT remain rather controversial. The theses therefore concludes that FTT is not due to the severity of its impacts appropriate economic measure.

The impact of Security Transaction Taxes (STTs) on the financial market has been studied by authors for decades, showing mixed results between positive, negative, or insignificant relations between STTs and financial volatility. This thesis adds a new approach to previous studies by taking an innovative long-term approach to the topic, analysing the effect of both the New York State STT (1905 – 1981) and the United States STT (1914 – 1966) on volatility in the New York Stock Exchange (NYSE) and NASDAQ as measured by the S&P500 Index. The period of investigation is from 1950 to 2019. This analysis reveals a negative relation between the NY STT and volatility when those are computed in long periods of time, implying that the presence (and increase) of STTs lead to a reduced volatility in the financial market. When breaking the analysis down into shorter periods of time the relationship between STTs and financial volatility proved to be insignificant. At the same time, the US STT is not statistically significant neither in the long-term nor in any of the separated shorter analysed periods. This thesis therefore highlights the relevancy of performing long-term studies rather than short-term ones which has been the focus of previous research.

With respect to foreign currency exchange markets, most governments would favour a stable exchange rate over a volatile exchange rate. This is also true for South Africa where volatile movements in the South African Rand pose challenges to industries, businesses and Government alike. There are a multitude of factors that affect the volatility of the South African Rand. These factors are difficult to identify, manage individually and measure. There are several tools that are available to manipulate and control foreign exchange rates in an attempt to reduce volatility; one such tool is the currency transaction tax. Spahn tax is one such form of currency transaction tax. The precursor to Spahn tax is Tobin tax. As a result of many criticisms levelled against Tobin tax, Spahn expanded on this original idea and made a few modifications to address some of the concerns. Spahn focused on creating a two-tier tax base where transactions falling within a normal and reasonable trading range would be taxed at a nominal amount and transactions that fall outside of the band would be taxed at a higher punitive rate. The trading band, or range, would be adjustable though market dynamics on a daily basis using a moving average. No country has implemented Spahn tax yet. The implementation of such a tax would have strong revenue-generating potential. A modification of such a tax with only a punitive rate and a wide trading band could be considered for South Africa. However, in being prudent South Africa does not appear to be in a position to be the first country to implement Spahn tax. There are too many market risks associated with the introduction Spahn tax that cannot be ignored. / Dissertation (MCom)--University of Pretoria, 2012. / Taxation / unrestricted

This paper investigates whether Tobin tax would be effective to reduce exchange rate volatility. When the rational speculators observe different temporarily shocks and take Tobin tax into account, the exchange rate will have either stable or unstable path through speculators’ changing optimal holdings. If the effect of current account shock dominates the effect of interest differential shock, the imposition of tax will stabilize the currency. This result is consistent with Tobin’s view. On the contrary, if the effect of interest differential shock dominates the effect of current account shock, the imposition of tax will destabilize the currency. The best policy in this case is to let international capitals move freely.

Submitted by Rodrigo dos Santos Barbosa (rdsbar@gmail.com) on 2016-06-13T19:54:58Z No. of bitstreams: 1 Tese.pdf: 895418 bytes, checksum: 64d50c7a9b78e9d3f89b6737e052eb58 (MD5) / Approved for entry into archive by Letícia Monteiro de Souza (leticia.dsouza@fgv.br) on 2016-06-13T21:06:35Z (GMT) No. of bitstreams: 1 Tese.pdf: 895418 bytes, checksum: 64d50c7a9b78e9d3f89b6737e052eb58 (MD5) / Made available in DSpace on 2016-06-13T22:04:05Z (GMT). No. of bitstreams: 1 Tese.pdf: 895418 bytes, checksum: 64d50c7a9b78e9d3f89b6737e052eb58 (MD5) Previous issue date: 2016-05-17 / My dissertation focuses on dynamic aspects of coordination processes such as reversibility of early actions, option to delay decisions, and learning of the environment from the observation of other people’s actions. This study proposes the use of tractable dynamic global games where players privately and passively learn about their actions’ true payoffs and are able to adjust early investment decisions to the arrival of new information to investigate the consequences of the presence of liquidity shocks to the performance of a Tobin tax as a policy intended to foster coordination success (chapter 1), and the adequacy of the use of a Tobin tax in order to reduce an economy’s vulnerability to sudden stops (chapter 2). Then, it analyzes players’ incentive to acquire costly information in a sequential decision setting (chapter 3). In chapter 1, a continuum of foreign agents decide whether to enter or not in an investment project. A fraction λ of them are hit by liquidity restrictions in a second period and are forced to withdraw early investment or precluded from investing in the interim period, depending on the actions they chose in the first period. Players not affected by the liquidity shock are able to revise early decisions. Coordination success is increasing in the aggregate investment and decreasing in the aggregate volume of capital exit. Without liquidity shocks, aggregate investment is (in a pivotal contingency) invariant to frictions like a tax on short term capitals. In this case, a Tobin tax always increases success incidence. In the presence of liquidity shocks, this invariance result no longer holds in equilibrium. A Tobin tax becomes harmful to aggregate investment, which may reduces success incidence if the economy does not benefit enough from avoiding capital reversals. It is shown that the Tobin tax that maximizes the ex-ante probability of successfully coordinated investment is decreasing in the liquidity shock. Chapter 2 studies the effects of a Tobin tax in the same setting of the global game model proposed in chapter 1, with the exception that the liquidity shock is considered stochastic, i.e, there is also aggregate uncertainty about the extension of the liquidity restrictions. It identifies conditions under which, in the unique equilibrium of the model with low probability of liquidity shocks but large dry-ups, a Tobin tax is welfare improving, helping agents to coordinate on the good outcome. The model provides a rationale for a Tobin tax on economies that are prone to sudden stops. The optimal Tobin tax tends to be larger when capital reversals are more harmful and when the fraction of agents hit by liquidity shocks is smaller. Chapter 3 focuses on information acquisition in a sequential decision game with payoff complementar- ity and information externality. When information is cheap relatively to players’ incentive to coordinate actions, only the first player chooses to process information; the second player learns about the true payoff distribution from the observation of the first player’s decision and follows her action. Miscoordination requires that both players privately precess information, which tends to happen when it is expensive and the prior knowledge about the distribution of the payoffs has a large variance. / A presente tese concentra-se em aspectos dinâmicos de processos que envolvem coordenação entre agentes em ambientes com interação estratégica. Propomos utilizar os chamados global games para estudar a capacidade de uma Tobin tax elevar a probabilidade de sucesso em um ambiente em que investidores internacionais sujeitos a choques de liquidez precisam coordenar suas decisões de investimento (capítulo 1), e reduzir a vulnerabilidade de uma economia aberta a fluxos internacionais de capitais a sudden stops (capítulo 2). Também, investigamos o problema da aquisição de informação em jogos sequenciais com informação incompleta e complementaridade em ações (capítulo 3). No capítulo 1, agentes estrangeiros decidem se entram ou não em um projeto, cujo sucesso depende em parte da capacidade dos mesmos em coordenarem suas escolhas. Uma fração λ desses investidores é afetada por restrições de liquidez no segundo período do modelo e é forçada a se retirar do projeto ou impedida de entrar, dependendo de suas respectivas escolhas no primeiro período. Agentes não afetados pelo choque de liquidez possuem a opção de reavaliar decisões tomadas no primeiro estágio do jogo. É assumido que a probabilidade de sucesso do projeto de investimento é crescente no volume total de capital que a economia recebe, mas decrescente no volume de capitais que deixa a economia no segundo período. Na ausência de choques de liquidez (λ = 0), o volume de capital que é recebido em um estado pivotal para o sucesso do projeto de investimento independe da existência de um imposto sobre capitais de curto prazo. Como tal imposto sempre desestimula saídas de capitais, uma Tobin tax sempre favorece as chances de sucesso em uma economia em que λ = 0. Contudo, na presença de choques de liquidez, o volume total de investimento que a economia recebe torna-se decrescente em um imposto incidente sobre capitais de curto prazo. Neste caso, uma Tobin tax pode prejudicar as chances do processo de coordenação ser bem sucedido, caso o benefício de reduzir o volume de saída de capitais não seja suficientemente grande. O capítulo 2 estuda os efeitos de uma Tobin tax no mesmo cenário do capítulo 1, porém considera que a extensão da restrição de liquidez a que os agentes podem estar sujeitos é aleatória. Neste modelo, identificamos condições sob as quais uma Tobin tax reduz a probabilidade de se observar um sudden stop e eleva o bem estar no único equilíbrio de uma economia onde a probabilidade de ocorrência de um choque de liquidez é pequena, mas a magnitude de tal choque pode ser significativa. O capítulo final investiga o problema de aquisição de informação em um jogo sequencial com 2 agentes, externalidade informacional e complementaridade em ações. Demonstramos que, quando o custo de aquisição de informação é pequeno relativamente ao incentivo que os agentes possuem para coordenarem suas ações, apenas o primeiro jogador escolhe adquirir novas informações a respeito da distribuição dos payoffs, e o jogador 2 sempre segue a ação escolhida pelo jogador 1. Probabilidade positiva de se observar divergência em ações requer que ambos os jogadores processem informação privadamente, o que tende a ocorrer quando o custo de aquisição de informação é baixo e a distribuição a priori dos payoffs possui variância elevada.

Never before in history has the amount of international trade been higher or more efficient than it is today. The fastest growing type of trade is the speculative currency trading, searching for instant profit based only on the anticipation of the variations in currency exchange rates. When currency speculation becomes an influential part of the capital flows it becomes harmful and creates instability of currency systems. Exchange rates starts to fluctuate due to the will and anticipation of speculators rather than the economic health of the country associated with the currency. This has led to recurring currency crises all over the world and an increased interest in regulatory mechanisms. One of the most discussed mechanisms proposed to handle this harmful evolution of the foreign exchange markets is the Currency Transaction Tax (CTT). The CTT stipulates a low tax (0.1 per cent) on all currency transaction to curb the incitement of short-term speculation based on a large amount of smaller transactions. The purpose of this thesis is to examine whether an implementation of a CTT is compatible with the EU treaties. This purpose consists of two research questions; whether the CTT is in conformity with the substantive law of the EU, more precisely the free movements of capital, and if the CTT is in conformity with the Economic and Monetary Union (EMU) and the exclusive power of the European System of Central Banks (ESCB) over monetary policy. Since this thesis aims to identify if the CTT is in conformity with existing legislation, the traditional doctrinal method is used for identifying and analysing potential difficulties with the CTT and to interpret these provisions in the light of ECJ case law and literature. The thesis concludes that the CTT is in conformity with the EU treaties. It does however require the full cooperation of the ESCB and ECB to achieve the objectives; to create a more stable currency market. The CTT is ready to implement.