76 research outputs found
Tax Enforcement in an Agent-Based Model with Endogenous Audits
We generalize the classic Allingham and Sandmo’s model of tax evasion considering heterogeneous agents with different degrees of tax morale and matchable, as opposed to non-matchable, income. The Tax Agency evolves its control scheme, maximizing the revenues from fines, and takes into account some minimal information on the taxpayers. We compare different audit policies and find that the most effective scheme remarkably depends on the way agents update the subjective probability of being audited, on the distribution of matchable income in the population as well as on the level of tax morale. Hence, different features of societies and taxpayers’ behaviors not only affect the compliance rate, as expected, but require the Tax Agency to alter its audit policy in a context-dependent way. In particular, high revenues are obtained performing random audits when agents think they are directed towards peculiar individuals and, conversely, should be biased towards low declarations when taxpayers believe audits are nonspecific or random
Nano-surgery at the leukocyte–endothelial docking site
The endothelium has an important role in controlling the extravasation of leukocytes from blood to tissues. Endothelial permeability for leukocytes is influenced by transmembrane proteins that control inter-endothelial adhesion, as well as steps of the leukocyte transmigration process. In a cascade consisting of leukocyte rolling, adhesion, firm adhesion, and diapedesis, a new step was recently introduced, the formation of a docking structure or “transmigratory cup.” Both terms describe a structure formed by endothelial pseudopods embracing the leukocyte. It has been found associated with both para- and transcellular diapedesis. The aim of this study was to characterize the leukocyte–endothelial contact area in terms of morphology and cell mechanics to investigate how the endothelial cytoskeleton reorganizes to engulf the leukocyte. We used atomic force microscopy (AFM) to selectively remove the leukocyte and then analyze the underlying cell at this specific spot. Firmly attached leukocytes could be removed by AFM nanomanipulation. In few cases, this exposed 8–12 μm wide and 1 μm deep footprints, representing the cup-like docking structure. Some of them were located near endothelial cell junctions. The interaction area did not exhibit significant alterations neither morphologically nor mechanically as compared to the surrounding cell surface. In conclusion, the endothelial invagination is formed without a net depolymerization of f-actin, as endothelial softening at the site of adhesion does not seem to be involved. Moreover, there were no cases of phagocytotic engulfment, but instead the formation of a transmigratory channel could be observed
Income tax buyouts and income tax evasion
A tax buyout is a contract between tax authorities and a tax payer which reduces the marginal income tax rate in exchange for a lump-sum payment. While previous contributions have focussed on labour supply, we consider the interaction with tax evasion and show that a buyout can increase expected tax revenues. This will be the case if (1) the audit probability is constant and the penalty for evasion is a function of undeclared income or (2) the penalty depends on the amount of taxes evaded, and authorities use information about income generated by the decision about a tax buyout offer when setting audit probabilities. Since individuals will only utilise a tax buyout if they are better off, higher tax revenues imply that such contracts can be Pareto-improving
Financial Satisfaction and (in)formal Sector in a Transition Country
This paper examines the relationship between working in the formal or informal sector and self-reported individual financial satisfaction in a country in transition. It does so by allowing for individual heterogeneity in terms of perceived financial insecurity and tax morale. The empirical analysis uses a dataset for Albania, a country in transition. The method applied is the ‘self-administered questionnaire’, which combines personal contacts with written questionnaire. The results indicate that, for most individuals, working in the informal sector has negative effects on their self reported financial satisfaction. For some individuals, however, this effect is positive. The characteristic defining these two groups of individuals is their attitude towards the perceived financial insecurity related to not paying taxes. These findings have important implications, in particular for transition countries with large informal sectors. Given the involuntary participation in the informal sector in these countries, the majority of individuals working in this sector will remain financially dissatisfied as long as they have no other social safety net
Adherens junctions connect stress fibres between adjacent endothelial cells
<p>Abstract</p> <p>Background</p> <p>Endothelial cell-cell junctions maintain endothelial integrity and regulate vascular morphogenesis and homeostasis. Cell-cell junctions are usually depicted with a linear morphology along the boundaries between adjacent cells and in contact with cortical F-actin. However, in the endothelium, cell-cell junctions are highly dynamic and morphologically heterogeneous.</p> <p>Results</p> <p>We report that endothelial cell-cell junctions can attach to the ends of stress fibres instead of to cortical F-actin, forming structures that we name discontinuous adherens junctions (AJ). Discontinuous AJ are highly dynamic and are increased in response to tumour necrosis factor (TNF)-α, correlating with the appearance of stress fibres. We show that vascular endothelial (VE)-cadherin/β-catenin/α-catenin complexes in discontinuous AJ are linked to stress fibres. Moreover, discontinuous AJ connect stress fibres from adjacent cells independently of focal adhesions, of which there are very few in confluent endothelial cells, even in TNF-α-stimulated cells. RNAi-mediated knockdown of VE-cadherin, but not zonula occludens-1, reduces the linkage of stress fibres to cell-cell junctions, increases focal adhesions, and dramatically alters the distribution of these actin cables in confluent endothelial cells.</p> <p>Conclusions</p> <p>Our results indicate that stress fibres from neighbouring cells are physically connected through discontinuous AJ, and that stress fibres can be stabilized by AJ-associated multi-protein complexes distinct from focal adhesions.</p
Network-Based Policies Versus Tax Evasion
This chapter explores the optimal income tax audit strategies from a social planner’s perspective, whose objective is to minimize the aggregated tax evasion of a given society. Agents live in a social-cohesive network with homophilic linkages, meaning individuals connect only with people who are akin to them. Further, each period individuals share their memories about past audits and consequently update their subjective probability of being audited. The Tax Agency finds that networkbased audit policies are inefficient, in the sense that they are just as good as random. Thus, the social planner credibly announces that, from now on, audit rates will be linearly proportionate to the agent’s income, making richer people more prone of being audited. Audit rates are now endogenous and heterogeneous among agents, making it possible for the Tax Agency to find an optimal network-based policy following a local-average strategy where a “key sector” of society is predominantly audited every period. Following this strategy, under a dynamic framework, the Nash Equilibrium for the average subjective audit rate is swiftly raised after just a fewfiscal years. The enhanced subjective audit rate, in turn, unfolds as a larger tax revenue collection and a significant deterrence of income tax evasion
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