Threshold Effects And Perturbative Unification

We discuss the effect of the renormalization procedure in the computation of the unification point for running coupling constants. We explore the effects of threshold--crossing on the $\beta$--functions. We compute the running of the coupling constants of the Standard Model, between $m_Z$ and $M_P$, using a mass dependent subtraction procedure, and then compare the results with $\bar{MS}$, and with the $\theta$-- function approximation. We also do this for the Minimal Supersymmetric extension of the Standard Model. In the latter, the bounds on susy masses that one obtains by requiring perturbative unification are dependent, to some extent, on the procedure.Comment: 22 pages, REVTEX-2.1, 6 Post-Script figures are include

The Role Of Tax And Transfers In Reducing Personal Income Inequality In Europeís Regions: Evidence From EUROMOD

In this paper we use statistical tools and graphic devices in order to give a comprehensive picture of income inequality levels in a set of 100 EU-15 regions at the end of the XX century before and after the operation of the tax-benefit. Our analysis is based on EUROMOD, the first multi-country tax-benefit model built with a common framework that includes detailed information on taxes and benefits paid and received by individuals and/or households from samples that are representative for the 15 EU countries. Our analysis focuses on intraregional inequality and it explores the relationship between regional inequality levels (both in market incomes and disposable incomes) and economic performance. Our main findings indicate that tax-benefits systems in Europe notably reduce market inequality in all EU regions and that the size of this reduction (i.e. redistributive effect) depends crucially on (i) the market inequality level of the region (positively), (ii) the relative economic performance of the region in the country (negatively) and (iii) the country to which the region belongs.European Union, Regions, inequality, redistribution, economic performance

Income inequality comparisons with dirty data: the UK and Spain during the 1980s

Inequality comparisons between countries and over time should take into account problems of data imperfection. We examine the contrasting experience of the UK and Spain during the 1980s in terms of the distribution of disposable income. We consider whether the apparent divergence in inequality could be attributable to deficiencies in income data including under-reporting