Uribe (2021) investigates the nature and empirical importance of monetary policy shocks that produce neo-Fisherian dynamics, i.e. move interest rates and inflation in the same direction over the short run. To that end, the author estimates a standard small-scale New-Keynesian model with price stickiness and habit formation, augmented with seven structural shocks.

Three of the shocks are to monetary policy, which is described by the following policy rule:

1+ItΓt=[A(1+ΠtΓt)αt(YtXt)αy]1γI(1+It1Γt1)γIeztm,

where It the nominal interest rate, Yt is aggregate output, Πt is the inflation rate, Γt is the inflation-target, Xt is a nonstationary productivity shocks, and ztm is a stationary interest-rate shock. The inflation target is defined as

Γt=Xtmeztm2,

where Xtm and ztm2 are permanent and transitory components of the inflation target. It is assumes that Xtm and Xt grow at a rates gtm and gt, respectively.

There are two preference shocks affecting the lifetime utility function of the representative household, given by

E0t=0βteξt{[(CtδC~t1)(1eθtht)χ]1σ11σ},

where Ct is consumption, C~t is the cross sectional average of consumption, ht is hours worked, ξt is an intertemporal preference shock, and θt is a shock to labor supply.

In addition to Xt, there is also a stationary productivity shock zt, which affects the production technology according to

Yt=eztXthtα,

The five stationary shocks (ξt, θt, zt, ztm, and ztm2 ) and the growth rates of the two non-stationary shocks (gt and gtm) are all assumed to follow first-order autoregressive processes.

Uribe (2021) estimates the model using quarterly US data on three variables: per capita output growth (yt), the interest-rate-inflation differential (rt=itπt), and the change in the nominal interest rate (it). All variables are assumed to be observed with measurement errors.