This paper describes IZAΨMOD, the policy microsimulation model of the Institute for the Study of Labor (IZA). The model uses household microdata from the German Socio-Economic Panel Study and firm data from the German linked employer-employee dataset LIAB. IZAΨMOD consists of three components:...

The elasticity of taxable income (ETI) is often interpreted as a sufficient statistic to assess the welfare costs of taxation. Building on the conceptual framework of Chetty (2009), we show that this assertion does no longer hold for tax systems with deduction possibilities if (i) deductions...