Haavelmo's seminal 1943 paper is the first rigorous treatment of causality. In it, he distinguished the definition of causal parameters from their identification. He showed that causal parameters are de fined using hypothetical models that assign variation to some of the inputs determining...

In this paper, I introduce money in the standard labor-matching model (Mortensen and Pissarides 1999, Pissarides 2000). A double coincidence problem makes Fiat Money necessary as a medium of exchange. In the long-run, a rise in the rate of money growth leads to higher inflation and higher...

We build a theoretical model to study whether a minimum wage can be welfare-improving if it is implemented in conjunction with an optimized nonlinear income tax. We consider this issue in a framework where search frictions on the labor market generate unemployment. Workers differ in...

This paper examines the correlated random coefficient model. It extends the analysis of Swamy (1971, 1974), who pioneered the uncorrelated random coefficient model in economics. We develop the properties of the correlated random coefficient model and derive a new representation of the variance...

This paper revisits the normative properties of search-matching economies when homogeneous workers have concave utility functions and wages are bargained over. The optimal allocation of resources is characterized first when information is perfect and second when search effort is not observable....

This paper characterizes optimal non-linear income taxation in an economy with a continuum of unobservable productivity levels and endogenous involuntary unemployment due to frictions in the labor markets. Redistributive taxation distorts labor demand and wages. Compared to their efficient...

This paper builds a macroeconomic model of equilibrium unemployment in which firms persistently face difficulties in selling their production and this affects their decisions to create jobs. Due to search-frictions on the product market, equilibrium unemployment is a U-shaped function of the...

This paper characterizes the optimal redistributive taxation when individuals are heterogeneous in two exogenous dimensions: their skills and their values of non-market activities. Search-matching frictions on the labor markets create unemployment. Wages, labor demand and participation are...

This paper characterizes optimal income taxation when individuals respond along both the intensive and extensive margins. Individuals are heterogeneous across two dimensions: specifically, their skill and disutility of participation. Preferences over consumption and work effort can differ with...

We propose a canonical model of optimal nonlinear redistributive taxation with matching unemployment. In our model, agents are endowed with different skill levels and labor markets are perfectly segmented by skill. The government only observes negotiated wages. More progressive taxation leads to...