In the public debate, it is argued that Poland avoided a massive drop in output during the 2008/2009 economic crisis in part thanks to substantial nominal zloty’s depreciation against the euro. The Polish case is often contrasted with Slovakia that adopted the euro in January 2009 and, since the Ecofin Council decision in summer 2008, exhibited virtually no nominal exchange rate volatility while facing deep losses in output. In this paper we attempt to validate this contrast by reversing the roles, i.e. checking if Poland really would have faced the same drop – and Slovakia would have remained relatively resilient – if it had been Poland, not Slovakia, that adopted the euro at that point. Our counterfactual simulations based on a New Keynesian DSGE model indicate that, indeed, the Polish tradable output could have been 10‒15 percent lower than actually observed in 2009, while the Slovak one – approximately 20 percent higher. This asymmetry results mainly from structural differences between the two economies, such as size, openness, share of nontradable sector and foreign trade elasticities. The difference of this size would have been short-lived (3‒4 quarters), and the difference of the nontradable output would have been of much lower magnitude.

We attempt to apply a New Keynesian open economy model to simulate the economic consequences of influenza epidemic in Poland and measure the output loss (indirect cost) related to this disease. We introduce a negative health shock on the supply side of the economy and demonstrate that such a shock – implemented as a reduction in labour utilisation under unchanged labour cost – is not equivalent to negative labour supply shock. As expectational effects may hypothetically play a significant role in determining the economic cost of influenza, we attempt to endogenise the mechanism of epidemic in the model for the rational expectations solution algorithm to take account for the possibility of epidemic. This attempt has failed for the standard SIR model of epidemic and for the standard Blanchard-Kahn-like local solution methods, as the SIR block is only consistent with Blanchard-Kahn conditions under herd immunity of the population. In the deterministic simulation with the number of infected given exogenously, the output loss resulting from influenza-related presenteeism and absenteeism was estimated at 0.004% of the steady state level on average in the period 2000‒2013. The simulated indirect cost in the New Keynesian model has turned out to be lower than the estimates that one could possibly obtain using the human capital approach. The reason for this discrepancy is the demand-oriented construction of the New Keynesian framework, and we treat this result as closer in notion to what the friction cost approach might suggest.

The Walters critique of EMU presumed that pro-cyclical country-specific real interest rates would incorporate significant macroeconomic instability in an environment of asymmetric shocks. The literature on optimum currency areas suggests a number of criteria to minimize this risk, such as market flexibility, high degrees of openness, financial integration or similarity in inflation rates. In this paper, we argue that an essential part of macroeconomic volatility in a monetary union’s member country also depends on the mechanism of forming expectations. This is mainly due to (i) the construction of ex ante countryspecific real interest rate, implying a strong or weak negative correlation with current inflation rate and (ii) anticipated (and hence smoothed) loss in competitiveness and boom-bust cycle. In a 2-region 2-sector New Keynesian DSGE model, we apply 5 different specifications of ex ante real interest rates, based on commonly considered types of expectations: rational, adaptive, static, extrapolative and regressive, as well as their hybrids. Our simulations show that rational expectations dominate the other specifications in terms of minimizing the volatility of the most macroeconomic variables. This conclusion is generally insensitive to which group of agents (producers or consumers) and which region (home or foreign) forms the expectations. It also turns out that for some types of expectations the Walters critique indeed applies, i.e. the system does not fulfil the Blanchard-Kahn conditions or the system’s companion matrix has explosive eigenvalues.

The model considered in the paper is defined as VAR with the prior distribution for parameters generated by the dynamic stochastic general equilibrium (DSGE) model. The degree of economic restrictions in the DSGE-VAR model is controlled by the weighting parameter. In the paper there is investigated the impact of the weighting parameter prior specifications for the posterior shape of impulse response functions (IRFs). In case of conditional models the paths of IRFs highly depend on the value of the weighting parameter that is set arbitrary. When considering full estimation with different prior types, means and gradual change in the dispersion the posterior time paths of IRFs are similar in models with high values of the marginal data density.