Pedro Teles

Banco de Portugal
R. Francisco Ribeiro 2
1150 Lisboa


NBER Working Papers and Publications

September 2017Should Robots be Taxed?
with Joao Guerreiro, Sergio Rebelo: w23806
We use a model of automation to show that with the current U.S. tax system, a fall in automation costs could lead to a massive rise in income inequality. This inequality can be reduced by raising marginal income tax rates and taxing robots. But this solution involves a substantial efficiency loss for the reduced level of inequality. A Mirrleesian optimal income tax can reduce inequality at a smaller efficiency cost, but is difficult to implement. An alternative approach is to amend the current tax system to include a lump-sum rebate. In our model, with the rebate in place, it is optimal to tax robots only when there is partial automation.
February 2011Unconventional Fiscal Policy at the Zero Bound
with Isabel Correia, Emmanuel Farhi, Juan Pablo Nicolini: w16758
When the zero lower bound on nominal interest rates binds, monetary policy cannot provide appropriate stimulus. We show that in the standard New Keynesian model, tax policy can deliver such stimulus at no cost and in a time-consistent manner. There is no need to use inefficient policies such as wasteful public spending or future commitments to inflate. We conclude that in the New Keynesian model, the zero bound on nominal interest rates is not a relevant constraint on both fiscal and monetary policy.

Published: Isabel Correia & Emmanuel Farhi & Juan Pablo Nicolini & Pedro Teles, 2013. "Unconventional Fiscal Policy at the Zero Bound," American Economic Review, American Economic Association, vol. 103(4), pages 1172-1211, June. citation courtesy of

September 2010Is Quantity Theory Still Alive?
with Harald Uhlig: w16393
This paper investigates whether the quantity theory of money is still alive. We demonstrate three insights. First, for countries with low inflation, the raw relationship between average inflation and the growth rate of money is tenuous at best. Second, the fit markedly improves, when correcting for variation in output growth and the opportunity cost of money, using elasticities implied by theories of Baumol-Tobin and Miller-Orr. Finally, the sample after 1990 shows considerably less inflation variability, worsening the fit of a one-for-one relationship between money growth and inflation, and generates a fairly low elasticity of money demand.

Published: Pedro Teles & Harald Uhlig & João Valle e Azevedo, 2016. "Is Quantity Theory Still Alive?," The Economic Journal, vol 126(591), pages 442-464. citation courtesy of

December 2007Nominal Debt as a Burden on Monetary Policy
with Ramon Marimon, Javier Díaz-Giménez, Giorgia Giovannetti: w13677
We characterize the optimal sequential choice of monetary policy in economies with either nominal or indexed debt. In a model where nominal debt is the only source of time inconsistency, the Markov-perfect equilibrium policy implies the progressive depletion of the outstanding stock of debt, until the time inconsistency disappears. There is a resulting welfare loss if debt is nominal rather than indexed. We also analyze the case where monetary policy is time inconsistent even when debt is indexed. In this case, with nominal debt, the sequential optimal policy converges to a time-consistent steady state with positive -- or negative -- debt, depending on the value of the intertemporal elasticity of substitution. Welfare can be higher if debt is nominal rather than indexed and the level of de...

Published: Javier Diaz-Gimenez & Giorgia Giovannetti & Ramon Marimon & Pedro Teles, 2008. "Nominal Debt as a Burden on Monetary Policy," Review of Economic Dynamics, Elsevier for the Society for Economic Dynamics, vol. 11(3), pages 493-514, July. citation courtesy of

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