As mudanças advindas com a popularização da tecnologia, com maior agudez no ambiente corporativo, associadas à assimetria informacional existente entre os contribuintes e as autoridades fiscais, ganharam novos contornos com a implementação do projeto SPED. Tal projeto trouxe em seu bojo a promessa de uma ferramenta com a capacidade de reduzir o tax gap, diferença entre o montante dos tributos devidos conforme a legislação e os tempestivamente recolhidos pelos contribuintes, em um ambiente saturado pela alta carga tributária e que, concomitantemente, atravessa um período de crise política e econômica. Neste cenário, os esforços das autoridades fiscais para a redução do tax gap tornam-se essenciais para que haja um maior volume arrecadatório sem que haja a criação de novos tributos. Diferentemente da maior parte dos estudos efetuados para análise do tax gap, este trabalho concentrou-se na análise de um tributo sobre o valor adicionado, o ICMS, tributo mais representativo do Produto Interno Bruto brasileiro. Nesse contexto, o objetivo deste estudo concentrou-se em avaliar como a influência das inovações técnicas e gerenciais introduzidas pelo projeto SPED impactou o tax gap do ICMS no Estado de São Paulo, sob a ótica dos agentes fiscalizadores. A partir da revisão da literatura e de sua análise exploratória foi desenvolvido o modelo teórico, testado pela técnica de modelagem de equações estruturais PLS-SEM. Os resultados mostraram que houve uma influência significativa dos determinantes do tax gap apresentados na literatura e do SPED no tax gap do ICMS paulista, com ênfase para as fiscalizações mais ágeis e abrangentes, maior acesso às informações dos contribuintes, influência na decisão do contribuinte em reduzir a parcela dos valores a sonegar e a identificação daqueles que declaram valores menores que os devidos. Os resultados contribuem para o desenvolvimento teórico do tax gap dos VATs, uma vez testadas e confirmadas a influência dos seus determinantes e do projeto SPED. / The changes coming by the popularization of technology, with greater acuteness in the corporate environment, associated with the informational asymmetry existing between taxpayers and tax authorities, have gained new contours with the implementation of the SPED project. This project brought in its wake the promise of a tool with the capacity to reduce the tax gap, the difference between the amount of taxes due according to the legislation and those that have been collected by taxpayers in an environment saturated by the high tax burden and which, at the same time, period of political and economic crisis. In this context, the efforts of the tax authorities to reduce the tax gap are essential to a higher collection volume without the creation of new taxes. Unlike most of the studies carried out to analyze the tax gap, this work focused on the analysis of a value-added tax, the ICMS, the most representative tax of the Brazilian Gross Domestic Product. In this way, the objective of this study was to understand how the determinants of the tax gap and the SPED project have helped the São Paulo government to reduce informational asymmetry with taxpayers, from the point of view of tax authorities. From the literature review and its exploratory analysis, the theoretical model was developed, tested by the structural equation modeling technique PLS-SEM. The results showed that there was a significant influence of the determinants of the tax gap presented in the literature and SPED in the ICMS´s tax gap of São Paulo, with emphasis on the more agile and comprehensive inspections, greater access to taxpayers\' information, influence on the taxpayer\'s decision to reduce the portion of the amounts to be withheld and the identification of those that declare lower amounts than those due. The results contribute to the theoretical development of the tax gap of the VATs once they have been tested and confirmed the influence of their determinants and the SPED project.

As mudanças advindas com a popularização da tecnologia, com maior agudez no ambiente corporativo, associadas à assimetria informacional existente entre os contribuintes e as autoridades fiscais, ganharam novos contornos com a implementação do projeto SPED. Tal projeto trouxe em seu bojo a promessa de uma ferramenta com a capacidade de reduzir o tax gap, diferença entre o montante dos tributos devidos conforme a legislação e os tempestivamente recolhidos pelos contribuintes, em um ambiente saturado pela alta carga tributária e que, concomitantemente, atravessa um período de crise política e econômica. Neste cenário, os esforços das autoridades fiscais para a redução do tax gap tornam-se essenciais para que haja um maior volume arrecadatório sem que haja a criação de novos tributos. Diferentemente da maior parte dos estudos efetuados para análise do tax gap, este trabalho concentrou-se na análise de um tributo sobre o valor adicionado, o ICMS, tributo mais representativo do Produto Interno Bruto brasileiro. Nesse contexto, o objetivo deste estudo concentrou-se em avaliar como a influência das inovações técnicas e gerenciais introduzidas pelo projeto SPED impactou o tax gap do ICMS no Estado de São Paulo, sob a ótica dos agentes fiscalizadores. A partir da revisão da literatura e de sua análise exploratória foi desenvolvido o modelo teórico, testado pela técnica de modelagem de equações estruturais PLS-SEM. Os resultados mostraram que houve uma influência significativa dos determinantes do tax gap apresentados na literatura e do SPED no tax gap do ICMS paulista, com ênfase para as fiscalizações mais ágeis e abrangentes, maior acesso às informações dos contribuintes, influência na decisão do contribuinte em reduzir a parcela dos valores a sonegar e a identificação daqueles que declaram valores menores que os devidos. Os resultados contribuem para o desenvolvimento teórico do tax gap dos VATs, uma vez testadas e confirmadas a influência dos seus determinantes e do projeto SPED. / The changes coming by the popularization of technology, with greater acuteness in the corporate environment, associated with the informational asymmetry existing between taxpayers and tax authorities, have gained new contours with the implementation of the SPED project. This project brought in its wake the promise of a tool with the capacity to reduce the tax gap, the difference between the amount of taxes due according to the legislation and those that have been collected by taxpayers in an environment saturated by the high tax burden and which, at the same time, period of political and economic crisis. In this context, the efforts of the tax authorities to reduce the tax gap are essential to a higher collection volume without the creation of new taxes. Unlike most of the studies carried out to analyze the tax gap, this work focused on the analysis of a value-added tax, the ICMS, the most representative tax of the Brazilian Gross Domestic Product. In this way, the objective of this study was to understand how the determinants of the tax gap and the SPED project have helped the São Paulo government to reduce informational asymmetry with taxpayers, from the point of view of tax authorities. From the literature review and its exploratory analysis, the theoretical model was developed, tested by the structural equation modeling technique PLS-SEM. The results showed that there was a significant influence of the determinants of the tax gap presented in the literature and SPED in the ICMS´s tax gap of São Paulo, with emphasis on the more agile and comprehensive inspections, greater access to taxpayers\' information, influence on the taxpayer\'s decision to reduce the portion of the amounts to be withheld and the identification of those that declare lower amounts than those due. The results contribute to the theoretical development of the tax gap of the VATs once they have been tested and confirmed the influence of their determinants and the SPED project.

This thesis deals with the measurement of tax evasion. The first part deals with the theory of tax evasion, its general, legislative and economic definition and its consequences. A special subsection is devoted to relation of the tax evasion and the shadow economy. The second part deals with the theory of tax evasion measurement and the last chapter focuses on shadow economy volume measurement and tax evasion measurement in the Czech Republic.

M.Comm. (International Accounting) / Recently, there has been a spate of reported cases of large corporate entities paying very little, or no income tax, despite the appearance of being profitable. Enron conducted a lot of business through special purpose vehicle (SPV) companies that were structured specifically for the purpose of paying very little, if any, corporate tax, without having to reduce reported book net profits to achieve this. A study in October 2012 of Starbucks by Reuters found that the company had reported no profits and had paid no income tax for the previous 3 financial years in the United Kingdom despite sales of 1.2 billion pounds. By comparison, McDonalds had to pay tax of 80 million pounds based on a turnover of 3.6 billion pounds, and KFC paid 36 million pounds in taxes on 1.1 billion pounds turnover in the United Kingdom. Another company highlighted for paying no tax is the giant Internet company, Ebay. In its latest financial period the company paid 1 million pounds in tax, on a turnover of 800 million pounds. Again complicated tax structures are at the centre of the tax computation. Consideration has to be given to the role played by the accounting standards, if any, in this scenario, and the extent of the role played by accounting treatments. One has to question if accounting treatments are enabling companies to consistently pay lower rates of tax than is statutorily required, through mechanisms like the raising of deferred tax, or whether it is simply a question of the relevant tax legislation being formulated in a way that allows taxable income to be lower than accounting income. The extent of this book-tax gap and the amount of tax actually paid by companies have been researched to a limited degree. Several studies have been conducted on the financial results from the 1990s, where a consistent decline in the collection of tax by authorities, despite the economic boom that was in existence at that time, has been shown. Research in the 2000s tends to confirm the continuance of this trend of an ever-increasing book-tax gap. The general consensus from the literature review conducted is that the divergence between book income and taxable income is a growing trend, and taxes actually paid by corporates are declining and are on average lower than statutory tax rates.

The Diploma Thesis deals with estimation of tax evation of value-added tax in the Czech Republic during 2006-2010. For the estimate we have used the concept of tax gap (in the case of VAT we speak about VAT gap), which is based on comparison of theoretical tax liability of the economy with the actual tax receipts. An international comparison of the Czech Republic VAT gap with available data of other countries has been made as well. The Thesis includes further description of tax evation types specific for VAT and other approaches to measurement of tax evation. Role of the shadow economy measurement used for tax evation estimates is accounted for.

This theses is about measuring the tax gap in the personal income tax in the Czech Republic. The first chapter deals with the theory of the tax gap, tax evasion and shadow economy. Second chapter describes methods that are used for measuring the shadow economy and the tax gap. The third part analyses the taxation of dependent and independent activity in the Czech Republic. The last, fourth part, estimates the tax gap in the personal income tax in the Czech Republic.

Revenue collection agencies across the world aim to maximise revenue collection by minimising tax noncompliance. The different types of tax noncompliance are collectively referred to as the tax gap phenomenon, which revenue collection agencies address by means of various enforcement approaches and capabilities. Much like any organisation, the resources required to execute these capabilities are finite and require accurate organisational decision-making in order to make optimal use thereof. Information technology, and specifically decision support systems (DSS), is critical in enabling this decision-making process. Using the Structuration Model of Technology, the information needs, demand and offerings of revenue collection agencies are explored given their objective of narrowing the tax gap phenomenon using DSS. Emphasis is placed on the manner in which IT is used to address taxpayer noncompliance, the way in which IT supports knowledge creation and subsequently also facilitate the decision-making process of tax practitioners, and also the different types of IT offerings made available to decision-makers in the form of DSS. In doing so, this research presents the results of a case study on the South African Revenue Service in which a conceptual decision support system framework is developed aimed at minimising the tax gap phenomenon. The research is conducted as a qualitative single case study and presented through a narrative analysis. The framework is systematically constructed as the research findings emerge and concluded by means of a framework validation and transfer ability test. The research result is a conceptual DSS framework acting as a reference point to other revenue collection agencies with the objective of addressing taxpayer noncompliance through DSS. / Jurisprudence / D. Phil. (Information Systems)

Revenue collection agencies across the world aim to maximise revenue collection by minimising tax noncompliance. The different types of tax noncompliance are collectively referred to as the tax gap phenomenon, which revenue collection agencies address by means of various enforcement approaches and capabilities. Much like any organisation, the resources required to execute these capabilities are finite and require accurate organisational decision-making in order to make optimal use thereof. Information technology, and specifically decision support systems (DSS), is critical in enabling this decision-making process. Using the Structuration Model of Technology, the information needs, demand and offerings of revenue collection agencies are explored given their objective of narrowing the tax gap phenomenon using DSS. Emphasis is placed on the manner in which IT is used to address taxpayer noncompliance, the way in which IT supports knowledge creation and subsequently also facilitate the decision-making process of tax practitioners, and also the different types of IT offerings made available to decision-makers in the form of DSS. In doing so, this research presents the results of a case study on the South African Revenue Service in which a conceptual decision support system framework is developed aimed at minimising the tax gap phenomenon. The research is conducted as a qualitative single case study and presented through a narrative analysis. The framework is systematically constructed as the research findings emerge and concluded by means of a framework validation and transfer ability test. The research result is a conceptual DSS framework acting as a reference point to other revenue collection agencies with the objective of addressing taxpayer noncompliance through DSS. / Jurisprudence / D. Phil. (Information Systems)