This thesis contains four papers in the area of Public Economics. Chapter 1 looks at producers' taxation in a model of vertically related oligopolies. Both ad valorem and specific taxes are considered and formulae expressing their effects on prices and profits are derived, showing how these depend on factors such as demand conditions, technology and market structure. Conditions for taxation to cause price overshifting and to raise profits are given. Also, tax instruments are compared in terms of the amount of revenue collected and the effect on the price for the final good. Chapter 2 applies the results of the previous paper to the analysis of tax reforms. Vertically related oligopolies result in welfare loss for two reasons. Firstly, upstream oligopolists set the price of the intermediate good above marginal cost and this causes aggregate production inefficiency. Secondly, downstream oligopolists introduce an additional price-cost margin. The analysis focuses on tax reforms, where the government aims at reducing the welfare loss by levying taxes and subsidies on producers while raising no revenue. Chapter 3 focuses on the design of income tax enforcement policies in a principalagent framework. The existing literature assumes risk neutral taxpayers while this chapter considers the case of risk averse agents by assuming a kinked linear utility function. When individuals have the same attitude towards risk, it is shown that the optimal policy is such that income reports below a given threshold are audited at the probability level just sufficient to induce truthful reporting, whereas those above it are not audited. This makes the effective tax schedule to be quite regressive. Instead, if attitudes towards risk vary across taxpayers, the numerical results show that the optimal audit policy causes only a limited regressive bias, for income reports above the threshold meet a positive probability of audit. Chapter 4 examines the Presumptive Income Coefficients (PIC) audit policy, a scheme recently introduced in the Italian tax code and aimed at reducing tax evasion in the non-corporate sector. The tax agency applies the PIC to observable production costs to get an estimate of taxpayer's income, or presumptive income. The probability of audit is then dependent on the gap between presumptive and reported income. This issue is examined in a setting where the game between the taxing authority and taxpayers is modelled in a principal-agent framework.

Chapter 2, titled "Hotelling Tax Competition" shows how competition among governments for mobile firms can bring about excessive differentiation in levels of taxation and public good provision. Hotelling's Principle of Minimum Differentiation is applied in the context of tax competition and shown to be invalid. Instead, when an equilibrium exists, differentiation of public good provision is maximized. Non-existence of equilibrium, which is possible, is a metaphor for intense tax competition. The chapter also shows that, to some extent, perfect tax discrimination presents a solution to the existence problem created by Hotelling tax competition, but that the efficiency problem of Hotelling tax competition is exacerbated. Chapter 3 shows how the institutional rules imposed on its signatories by the GATT created a strategic incentive for countries to liberalize gradually. Ree trade can never be achieved when punishment for deviation from a trade agreement is limited to a 'withdrawal of equivalent concessions' , the most severe form of punishment allowed (Article XXVIII). Retaliation is not allowed to entail higher tariffs than those set by the initial deviant. If, in addition, tariff bindings (Article 11) limit an initial deviation from an agreement in a similar way, then efficient self-enforcing tariff reductions must proceed in a series of steps or 'rounds'. Chapter 4 provides an answer to the question "Why are trade agreements regional? " It argues that free trade agreements (FTAs) are regional because, in their absence, optimal tariffs are higher against (close) regional partners than (distant) countries outside the region. Optimal tariffs shift rents from foreign firms to domestic citizens. Lower transport costs imply higher rents and therefore higher tariffs. So regional FTAs have a higher payoff than non-regional FTAs. Therefore, only regional FTAs may yield positive gains when sponsoring an FTA is costly. To analyze equilibrium, standard theory of non-cooperative networks is extended to allow for asymmetric players. Naive best response dynamics show that 'trade blocks can be stepping blocks' for free trade.

The public-private partnership (PPP) arrangements require the optimization of risk allocation between the public and private sectors in order to achieve the best net present value (NPV). Many researchers mentioned that the risk events of a PPP infrastructure projects are interdependent over project life cycle. Sterman (1992) stated that a large-scale construction project that is complex and has highly dynamic and interdependent risks and uncertainties over long-term project life cycle. Williams (2002) also mentioned that the risk usually interact each other with nonlinear relationships over time in a complex project. Dey and Ogunlana (2004) contended that there is a need to analyze risk interactions of complex infrastructure projects such as build-operate-transfer (BOT) projects over their long-term project life. In modern approaches to PPP project risk management, experts assume risk factors are independent and ignore the risk interaction effects over project life cycle, so the project risks cannot be effectively managed and controlled. The researcher proposed a modelling approach that used a risk network model applying System Dynamics (SD) techniques to estimate risk interaction effects on project NPV over time. The researcher used another SD model built on the risk network model to estimate the beneficial effects of bidding proposals on project NPV over time and to see how efficiently the risk effects can be reduced and the NPV performance can be improved. Then, the researcher applied appropriate stochastic analyses including mean-variance, mean semi-variance, stochastic dominance and expected-loss ratio to compare range values of NPV among different bidding proposals. A capable PPP concessionaire with the best project NPV performance can hence be selected. An industry case was applied to demonstrate SD decision models. The SD decision models have been validated through the behaviour reproduction test and multivariate sensitivity analysis. This proved that the proposed approach is robust and applicable to address real world problems to evaluate the longterm performance of a PPP project concessionaire

This thesis deals with the various ways taxpayers have employed to avoid paying tax on income, profits and gains and the responses of the judges and legislators. Each type of avoidance is followed from its first appearance to the present day, where appropriate. The respective manoeuvres of the taxpayers, on the one hand, and the Legislature, on the other, are chartered, as is the attitude of the courts. There are four sections. In the first, the various categories of tax avoidance arrangements that have been implemented over the years in the United Kingdom are examined. The second is concerned with international tax avoidance as seen from a United Kingdom perspective. Thirdly, the approach in the United Kingdom is compared with that of other countries, with particular reference to the United States of America, Canada and Australia. The last section analyses the role of the judges and examines the extent to which they have been prepared to look through the form of a transaction to consider the underlying substance. The role of the judges as makers of tax law is also considered. The way in which the subject was researched was to examine each category of tax avoidance in a chronological order, beginning with the first moves by the taxpayer, and charting the ensuing battle of wits between the taxpayer and the Legislature from the standpoint of those who have had to adjudicate on the process: the Judges.

Tax planning by large companies has been widely and publicly discussed due to its implications for the level of provision of public goods and more general social issues. In the U.K., tax avoidance, as estimated by Her Majesty’s Revenue and Customs’ anti-avoidance group, leads to several billion pounds of lost revenue each year. Consequently, the authorities implement tax investigation through risk classification assessments. The prospect of an adverse assessment may influence company directors when making tax planning decisions and similar risk concerns may influence shareholders in valuing tax planning activities. This study reports the results of an investigation of the relationship between firm value and tax planning whilst simultaneously considering corporate governance as a moderating influence. The sample of firms examined consists of non-financial London Stock Exchange-listed companies from 2005 to 2007. The results indicate a negative relationship between firm value and tax planning activities which is unconditional upon corporate governance conditions for both persistent and non-persistent profit-making companies. This relationship can be further explained as being related to the permanent differences component of tax saving where firm value is reported as negatively related to permanent differences. The findings of this study contribute to the body of knowledge since there is a general dearth of published research study from outside the U.S. that investigates these relationships.

This thesis consists of three essays related to balance of payment or the external sector issues. These three essays include an analysis of a country’s current account and fiscal sustainability position, the role of external debt in economic growth, and the reserves and debt management. The main intention of the first essay (comprising Chapter 2) is to analyze the sustainability of the current account and fiscal position for high, middle and low income countries. This empirical analysis makes use of various panel unit root and cointegration tests, as well as fixed and random effects estimators. The results indicate that there is evidence of current account sustainability only for high-income countries indicating that the intertemporal budget constraints are being maintained. In contrast, the middle-income and low-income countries are found to be in an unsustainable current account position. In addition, this paper also finds that all groups of countries have a slow phase of convergence towards equilibrium which suggests that all countries are vulnerable to any sudden shock or stop. Besides that, there is evidence of sustainability on fiscal policy for the high and middle groups of countries. Chapter 3 investigates the issue of whether external debt contributes to expansion in economic growth. This chapter attempts to answer this question by analyzing 31 developing countries over a period of 36 years (1970-2005). The results reveal that the accumulation of external debt is associated with a slowdown in the economies of the developing countries. Besides this, we find evidence that debt service ratio does not crowd out the investment rate in developing countries. In other words, even though the external debt is negatively associated with economic growth, countries are found to be safe from being in the debt overhang hypothesis. However, the negative effect could be interpreted as the main symptom of a country before it becomes involved in the debt overhang problem. In addition, fiscal balance, iii government revenue, openness, and domestic credits are found to have a positive effect on investment and, to a lesser extent, economic growth. Furthermore, there is evidence to support the existence of spatial dependence in the growth model, suggesting the existence of positive spillover effect of growth among the neighbouring countries. This suggests that countries are found to have positive correlation with their neighbours’ economic growth. The main analytical contribution of the final chapter, which is chapter 4, is to analyze the cost of jointly holding reserves and sovereign debt decision. By analyzing the impact of holding reserves and sovereign debt on sovereign credit ratings, this provides the evidence of the costs of holding reserves and debt with respect to credit risk. As predicted by theory, the international reserves-holding is associated with good sovereign credit ratings as well as lower credit risk while the sovereign debtholding leads to a lower sovereign credit rating and high credit risk. This implies that reducing (repaying) their sovereign debts is the best decision for countries to keep and maintain a good credit risk reputation. Meanwhile, the benefit of holding reserves has crowded out the cost of holding short-term debt, resulting in a net positive effect on sovereign ratings. This could imply that a country should hold more reserves with regard to the level of short-term debt which is a highly vulnerable liability for a country. The results reveal that the adequate level of international reserves in month of imports is slightly higher than with the conventional rule which at 3 month of imports.

Many governments are struggling with inadequate tax revenue and increasing tax gaps. Consequently, changing behaviour of non-compliant taxpayers as small and medium enterprises (SMEs) because of their tax revenue potential and non-compliance behaviour is essential. This thesis examined the impact of corporate income tax penalty incidence, retributive justice, procedural justice, the interaction between retributive and procedural justice on corporate income tax compliance behaviour. Also, the thesis analysed whether corporate income tax compliance costs affect SMEs tax compliance behaviour. Laboratory experimental methods found corporate income tax penalties levied on individual tax managers might be more effective than corporate income tax penalties charged on corporates. Also high tax compliance costs may decrease tax compliance levels. Likewise, a survey method discovered perceptions of retributive and procedural justice might associate with tax compliance behaviour. However, a perception of procedural justice can moderate the relationship between retributive justice and tax compliance. Conclusively, tax authorities may increase SMEs’ corporate income tax compliance by imposing corporate income tax penalties on tax managers, but these penalties should be perceived to fit the crime of corporate tax non-compliance and imposed through fair procedures. Also, the authorities may increase SMEs’ corporate tax compliance by decreasing tax compliance costs. Shortly, the thesis contributes to the limited tax literature on corporate income tax compliance, procedural and retributive justice and usage of real taxpayers in an experiment.

This study investigates the public sector external auditing (PSA) phenomenon in Tanzania, and seeks to understand the role of PSA, and the conditions in which it operates. In recent years, Tanzania has shown increased recognition of the contribution PSA makes to accountability, performance and the fight against corruption (CAGT, 2007). While empirical evidence to support this recognition is lacking in Tanzania, the literature review revealed mixed findings. Furthermore, the study responds to calls for more PSA studies in developing countries (Goddard, 2010) in general (Leung, White and Cooper, 2011) and those which adopt critical interpretive approaches (Baker and Bettner, 1997). The study adopts and implements a critical interpretive research strategy in fieldwork undertaken at the National Audit Office of Tanzania (NAOT). Specifically, it employs the grounded theory method (GTM) as an interpretive approach and strategically accommodates critical thinking in questioning and interpreting the case under study (Laughlin, 1995; Gibson, 2007). It also adopts elements of Habermas’ critical theory (HCT) as a lens through which interpretively field gained understanding is extended (Habermas, 1987). This study’s findings indicate that PSA in Tanzania encountered colonising tendencies because of weak working relationship between the NAOT and other accountability agencies, inconsistencies in governance and politics, the culture of corruption and secrecy, dependence on foreign financing and mimicking of foreign models. To coexist within this colonising environment, managing colonising tendencies appeared to be the core strategy for both the government and external auditors. While the government appeared to manage NAOT appearance and exploited the legitimising features of PSA, external auditors manoeuvred within colonising tendencies and attempted to maintain the ‘audit supremacy’ image. External auditors managed their relationship with auditees and the complexities of PSA roles. Managing colonising tendencies resulted into obscured subordination of PSA, contributing to cosmetic accountability and growing public interest in PSA. This research contributes to the understanding of the role and conditions shaping PSA in a developing country. It provides field-based evidence that maintaining an appearance of SAI’s ‘supremacy’ without resolving problems in the underlying power relations leads to superficial contributions from PSA. It also contributes to critical interpretive research in developing countries. Exploiting the pragmatic nature of grounded theory (GT), the research provides a practical demonstration of accommodating critical theory in a GTM. Finally, the colonisation thesis in HCT helped the researcher to develop a societal extension of the emergent theory, which also extended the thesis by highlighting external auditors’ responses to colonisation.

The effect of public investment on economic growth is a popular topic in economic literature. Although there are endogenous growth models that incorporate public expenditure as a factor that promotes growth, findings in empirical literature provide conflicting results. This thesis contributes to this debate by providing a comprehensive analysis of the relationship between public investment and development by using a new panel dataset for Turkish provinces. For analyses, public investment is disaggregated as energy infrastructure, city infrastructure and security, education, health, transportation and communication, agriculture, mining, manufacturing, tourism and housing. The outcome variables are chosen as economic growth rate, the gross enrolment rate for primary and middle school, and the infant mortality rate. With regard to the econometric method, the fixed-effects technique is chosen. The dependent variables are calculated as the five-year forward moving averages of the outcome variables. Standard errors are corrected for serial correlation, cross-sectional dependence and heteroscedasticity. Findings in this thesis suggest that public investments in education, agriculture, tourism and energy infrastructure are associated with higher growth rates. There does not appear to be any statistical relationship between public city infrastructure and security investment and economic growth. However, public city infrastructure and security investment is related to the long-run gross enrolment rate positively, and the long-run infant mortality rate negatively. Additionally, public investment in energy infrastructure appears to have a negative relationship with the long-run infant mortality rate. Finally, results show that public investment in mining, transportation and communication are negatively related to the long run growth. The results provide partial support for the predictions of the model in Barro (1990) in the second chapter and the development literature in the third and the fourth chapters. Public policies in the sectors mentioned above arise as a factor that has an impact on the outcome of public investment. Post-estimation diagnostics and robustness analyses provide statistical evidence that support the findings.

This thesis attempts to identify important factors that may affect the pricing and the probability of default of high yield bonds offered by shipping companies; and factors that may influence the pricing and the probability of underpricing of shipping US initial public offerings (IPOs). The analysis is carried out through five chapters and each chapter covers a topic on its own so that it can be read independently of previous and subsequent chapters. Chapter 1 provides an overview of the shipping US public equity market for the period 1987-2010. It also considers the reasons for a shipping company to go public; the advantages and disadvantages of such a decision; and the role of underwriters in the IPO process. Finally, it provides a literature review on shipping equity capital markets. Chapter 2 presents an overview of the shipping US high yield bond market for the period 1992-2010; it discusses the seniority of shipping high yield bonds, and, the advantages and disadvantages for shipping companies that decide to issue high yield bonds. Next, the credit ratings, the yield premia and the probability of default for shipping high yield bonds are examined. Finally, it provides a synopsis of the restructuring options that shipping companies have in case of default. Chapter 3 investigates the factors that may explain the dynamics of yield premia on seasoned shipping high yield bonds. The analysis utilises 40 seasoned high yield bonds offered by 32 shipping companies for the period April 1998 - December 2002; and it employs a set of microeconomic, macroeconomic and, industry related factors. The methodology used is the fixed effects panel data regression model and the results of the study suggest that the dynamics of yield premia of seasoned shipping high yield bonds can be explained by: the credit rating; the term-to-maturity; the changes in earnings in the shipping market, as well as the changes in the yields on the 10-year US Treasury bonds and the Merrill Lynch single-B index. This chapter contributes to the existing ship finance literature in the following ways: first, it attempts to model the changes of yield premia on shipping high yield bonds in the secondary market, which is of interest to investors and traders since information on changes in yield premia can be used for investment and asset allocation purposes. Second, it distinguishes between high yield bond issues offered by listed and unlisted companies, as well as, defaulted and non-defaulted bond issues in order to examine whether there is any difference in the impact of the explanatory variables on the determination of yield premia. Third, the analysis employs a set of macroeconomic and industry related factors that have not been previously used in the ship finance literature. Finally, the results may have implications for shipping companies in the following ways: yield premia are indications of the possible cost level in order to enter the shipping high yield bond market and may affect the company's image; hence, shipping companies may be interested in the yield premia as they can affect their financing decision for future/further issuance of high yield bonds or their possible stepping to the equity capital market. Chapter 4 uses a binary logit model to predict the probability of default for high yield bonds issued by shipping companies for the period 1992-2004. The results suggest that two liquidity ratios, the gearing ratio, the amount raised over total assets ratio, and an industry specific variable are the best estimates for predicting default at the time of issuance. In - and out - of sample bootstrap tests further indicate the predictive ability and robustness of the model. This chapter contributes to the existing ship finance literature as for the first time the probability of default of shipping high yield bonds is predicted by employing a binary logit model. Investors may benefit from this research since, by employing easily accessible and quantifiable factors they can identify at the time of issuance a) which factors to look at when making investment decisions; b) issues that may have a high likelihood to default. At the same time, shipowners who offer high yield bonds can also identify and focus on the factors that are important in predicting the probability of default for their bond issues. Chapter 5 examines the extent that public information, available prior to the US initial public offering of shipping companies, is only partially incorporated in the final offer price set by the underwriters. The sample includes 51 shipping US initial public offerings for the period 1987-2008, and a set of prospecti and market specific characteristics is employed. The Ordinary-Least-Squared Regression results show that 20-53 percent of the variation in first day returns is explained by employing public available information known prior to the offer date; therefore, it can be argued that final offer prices of shipping US IPOs are only partially adjusted to broadly accessible information. Additionally, the probability of underpricing is examined and the logit model correctly predicts 90 percent of the entire sample, with in and out-of-sample bootstrap tests further supporting the robustness of the model. This chapter contributes to the existing ship finance literature by testing the hypotheses of partial adjustment (Benveniste and Spindt, 1989) and winner's curse (Rock, 1986) theories as an explanation for shipping US IPOs' initial day returns. Moreover, it uses variables that have not been previously employed in shipping IPOs studies and the probability of underpricing a shipping IPO is examined for the first time. Finally, the results of the study show that by employing readily available information known prior to the shipping IPO date, investors can identify the factors that affect the initial day returns and also predict the probability of underpricing a shipping IPO. Chapters I and 2 are parts of chapters 20 and 21 in the book "The Blackwell Companion to Maritime Economics" (Grammenos and Papapostolou, forthcoming (a), forthcoming (b)). Chapter 3 has been published in Transportation Research Part E: Logistics and Transportation Review (Grammenos, Alizadeh, and Papapostolou, 2007) and an earlier version was presented at the International Association of Maritime Economists (lAME) conference in Izmir, Turkey in 2004. Chapter 4 has been published in Transportation Research Part E: Logistics and Transportation Review (Grammenos, Nomikos, and Papapostolou, 2008) and an earlier version was presented at the International Association of Maritime Economists (lAME) conference in Limassol, Cyprus in 2005. Finally, chapter 5 has been submitted to Transportation Research Part E: Logistics and Transportation Review and it is under review.