論文

We consider the fiscal multiplier and spillover-the extent to which one country's government expenditure increases production at home and also in another foreign country, when the two countries are caught simultaneously in a liquidity trap. Using a standard new open economy macroeconomics (NOEM) model, we show that the fiscal multiplier and spillover are contrary to textbook economics. For the country where government expenditure takes place, the fiscal multiplier exceeds one, the currency depreciates, and the terms of trade worsen. The fiscal spillover is negative if the intertemporal elasticity of substitution in consumption is less than one, and positive if it is greater than one. Incomplete stabilization of marginal costs due to the existence of the zero lower bound is critical in understanding the effects of fiscal policy in open economies. These results remain unchanged even if we incorporate incomplete markets or endogenous capital into the model, but local currency pricing yields positive fiscal spillover irrespective of the size of the intertemporal elasticity of substitution. © 2013 Elsevier B.V.

How should monetary policy cooperation be designed when more than one country is simultaneously facing zero lower bounds on nominal interest rates? To answer this question, we examine monetary policy cooperation with both optimal discretion and commitment policies in a two-country model. We reach the following conclusions. Under discretion, monetary policy cooperation is characterized by the intertemporal elasticity of substitution (IES), a key parameter measuring international spillovers, and no history dependency. On the other hand, under commitment, monetary policy featureshistory dependence with international spillover effects. © 2010 Bank of Japan.

© 2015 John Wiley & Sons, Ltd. It is well known that there is a large degree of uncertainty around Rogoff's consensus half-life of the real exchange rate. To obtain a more efficient estimator, we develop a system method that combines the Taylor rule and a standard exchange rate model to estimate half-lives. Further, we propose a median unbiased estimator for the system method based on the generalized method of moments with non-parametric grid bootstrap confidence intervals. Applying the method to real exchange rates of 18 developed countries against the US dollar, we find that most half-life estimates from the single equation method fall in the range of 3-5 years, with wide confidence intervals that extend to positive infinity. In contrast, the system method yields median-unbiased estimates that are typically shorter than 1 year, with much sharper 95% confidence intervals. Our Monte Carlo simulation results are consistent with an interpretation of these results that the true half-lives are short but long half-life estimates from single-equation methods are caused by the high degree of uncertainty of these methods.

Copyright © 2018 The Authors. This paper considers the optimal degree of monetary discretion when the central bank conducts policy based on its private information about the state of the economy and is unable to commit. Society seeks to maximize social welfare by imposing restrictions on the central bank's actions over time, and the central bank takes these restrictions and the new Keynesian Phillips curve as constraints. By solving a dynamic mechanism design problem, we find that it is optimal to grant “constrained discretion” to the central bank by imposing both upper and lower bounds on permissible inflation, and that these bounds should be set in a history-dependent way. The optimal degree of discretion varies over time with the severity of the time-inconsistency problem, and although no discretion is optimal when the time-inconsistency problem is very severe, it is a transient phenomenon and some discretion is granted eventually.

© 2015 Elsevier Inc. The policy package known as Abenomics appears to have influenced the Japanese economy drastically, in particular, in the financial markets. In this paper, focusing on the aggressive monetary easing of Abenomics, the first arrow, we evaluate its role in guiding public perceptions on monetary policy stance through the management of expectations. In order to end chronic deflation, such as that which Japan has been suffering over the last two decades, policy regime change must be perceived by economic agents. Analysis using the QUICK survey system (QSS) monthly survey data shows that monetary policy reaction to inflation rates has been in a declining trend since the mid 2000s, implying intensified forward guidance well before Abenomics. However, Japan seems to have moved closer to a long-term liquidity trap, where even long-term bond yields are constrained by the zero lower bound. Consequently, no sizable difference in perceptions has been found before and after the introduction of Abenomics. Estimated changes in perceptions are not abrupt enough to satisfy "Sargent's (1982) criteria for regime change" termed by Eggertsson (2008). This poses a serious challenge to central banks: what is an effective policy option left under the long-term liquidity trap?

Deviations from long-run price stability are optimal in the presence of endogenous entry and product variety in a sticky-price model in which price stability would be optimal otherwise Long-run inflation (deflation) is optimal when the benefit of variety to consumers falls short of (exceeds) the market incentive for creating that variety-the desired markup; Price indexation exacerbates this mechanism. Plausible preference specifications and parameter values justify positive long-run inflation rates. However, short-run price stability (around this non-zero trend) is close to optimal, even in the presence of endogenously time-varying desired markups that distort the intertemporal allocation of resources. © 2014 Elsevier B.V.

How should monetary policy respond to a "global liquidity trap," where the two countries may fall into a liquidity trap simultaneously? Using a two-country New Open Economy Macroeconomics model, we first characterize optimal monetary policy, and show that the optimal rate of inflation in one country is affected by whether or not the other country is in a liquidity trap. We next examine how well the optimal monetary policy is approximated by relatively simple monetary policy rules. The interest-rate rule targeting the producer price index performs well in this respect.© 2013 Elsevier B.V.

© 2019 Elsevier B.V. Should the fiscal authority use forward guidance to reduce future policy uncertainty perceived by private agents? Using dynamic general equilibrium models, we examine the welfare effects of announcing future fiscal policy shocks and show that selective transparency is desirable — announcing distortionary future policy shocks can be detrimental to ex ante social welfare, whereas announcing non-distortionary shocks generally improves welfare. Sizable welfare gains are found with constructive ambiguity regarding the timing of a tax increase in a realistic fiscal consolidation scenario. However, being secretive about distortionary shocks is time inconsistent, and welfare loss from communication may be unavoidable.