Guided by a macroeconomic model in which non-energy commodity prices are endogenously determined, we apply a new factor-based identification strategy to decompose the historical sources of changes in commodity prices and global economic activity. The model yields a factor structure for commodity prices and identification conditions that provide the factors with an economic interpretation: one factor captures the combined contribution of shocks that affect commodity markets only through general-equilibrium forces. Applied to a cross-section of commodity prices since 1968, the theoretical restrictions are consistent with the data and yield structural interpretations of the common factors in commodity prices. Commodity-related shocks have contributed modestly to global economic fluctuations. RésuméÀ partir d'un modèle macroéconomique dans lequel les prix des produits de base non énergétiques sont déterminés de façon endogène, les auteurs appliquent une nouvelle stratégie d'identification factorielle pour décomposer les éléments à l'origine des variations des prix des produits de base et de l'activité économique mondiale observées par le passé. Le modèle génère une structure factorielle des prix des produits de base, ainsi que des conditions d'identification permettant de donner aux facteurs examinés une interprétation économique : un facteur unique rend compte de l'incidence combinée de chocs dont l'influence sur les marchés des produits de base s'exerce uniquement par l'entremise des effets d'équilibre général. Appliquées à un échantillon représentatif des prix des produits de base depuis 1968, les contraintes théoriques sont conformes aux données et cadrent avec une interprétation structurelle des facteurs communs influant sur les prix de ces produits. Les auteurs constatent que les chocs liés aux produits de base ont pesé modestement sur les fluctuations de l'économie mondiale. Classification JEL : E3, F4 Classification de la Banque : Modèles économiques ; Questions internationalescommodity storage, while section 5 uses the indirect common factor in a recursive out-of-sample forecasting exercise. Section 6 concludes. 2The Sources of Commodity Price Co-movement: Theory In this section, we present a model that characterizes the sources of commodity price co-movement. In particular, we show that the model yields a tractable factor structure for a cross-section of commodity prices, which permits an economic interpretation of the factors. 2.1Model of commodity prices The baseline model consists of households, a continuum of heterogeneous primary commodities, a sector that aggregates these commodities into a single intermediate commodity input, and a final goods sector that combines commodities, labor and technology into a final good. The HouseholdA representative consumer maximizes expected discounted utility over consumption ( ), labor supply ( ) and the amount of another input supplied to each commodity sector ( ( )) as follows:

We present a signalling theory of Quantitative Easing (QE) at the zero lower bound on the short term nominal interest rate. QE is effective because it generates a credible signal of low future real interest rates in a time consistent equilibrium. We show these results in two models. One has coordinated monetary and fiscal policy. The other an independent central bank with balance sheet concerns. Numerical experiments show that the signalling effect can be substantial in both models.

We study spillover effects of US uncertainty fluctuations using panel data from fifteen emerging market economies (EMEs). A US uncertainty shock negatively affects EME stock prices and exchange rates, raises EME country spreads, and leads to capital outflows from them. Moreover, it decreases EME output, while increasing their consumer prices and net exports. The negative effects on output, exchange rates, and stock prices are weaker, but the effects on capital and trade flows stronger, for South American countries compared to other EMEs. We present a model of a small open economy that faces an external shock to interpret our findings.JEL codes: C33, E44, E52, E58, F32, F41

In this paper, we establish three new facts about price-setting by multi-product firms and contribute a model that can explain our findings. On the empirical side, using micro-data on U.S. producer prices, we first show that firms selling more goods adjust their prices more frequently but on average by smaller amounts. Moreover, the higher the number of goods, the lower is the fraction of positive price changes and the more dispersed the distribution of price changes. Second, we document substantial synchronization of price changes within firms across products and show that synchronization plays a dominant role in explaining pricing dynamics. Third, we find that within-firm synchronization of price changes increases as the number of goods increases. On the theoretical side, we present a state-dependent pricing model where multi-product firms face both aggregate and idiosyncratic shocks. When we allow for firm-specific menu costs and trend inflation, the model matches the empirical findings. JEL Classification: E30; E31; L11.

In this paper, we establish three new facts about price-setting by multi-product firms and contribute a model that can explain our findings. Our findings have important implications for real effects of nominal shocks and provide guidance for how to model pricing decisions of firms. On the empirical side, using micro-data on U.S. producer prices, we first show that firms selling more goods adjust their prices more frequently but on average by smaller amounts. Moreover, the higher the number of goods, the lower is the fraction of positive price changes and the more dispersed the distribution of price changes. Second, we document substantial synchronization of price changes within firms across products and show that synchronization plays a dominant role in explaining pricing dynamics. Third, we find that within-firm synchronization of price changes increases as the number of goods increases. On the theoretical side, we present a state-dependent pricing model where multiproduct firms face both aggregate and idiosyncratic shocks. When we allow for firm-specific menu costs and trend inflation, the model matches the empirical findings.

We estimate international spillover effects of US Quantitative Easing (QE) on emerging market economies. Using a Bayesian VAR on monthly US macroeconomic and financial data, we first identify the US QE shock with non-recursive identifying restrictions. We estimate strong and robust macroeconomic and financial impacts of the US QE shock on US output, consumer prices, long-term yields, and asset prices. The identified US QE shock is then used in a monthly Bayesian panel VAR for emerging market economies to infer the spillover effects on these countries. We find that an expansionary US QE shock has significant effects on financial variables in emerging market economies. It leads to an exchange rate appreciation, a reduction in long-term bond yields, a stock market boom, and an increase in capital inflows to these countries. These effects on financial variables are stronger for the "Fragile Five" countries compared to other emerging market economies. We however do not find significant effects of the US QE shock on output and consumer prices of emerging markets.JEL codes: C31, E44, E52, E58, F32, F41, F42

Using an estimated DSGE model that features monetary and fiscal policy interactions and allows for equilibrium indeterminacy, we find that a passive monetary and passive fiscal policy regime prevailed in the pre-Volcker period while an active monetary and passive fiscal policy regime prevailed post-Volcker. Since both monetary and fiscal policies were passive pre-Volcker, there was equilibrium indeterminacy which resulted in substantially different transmission mechanisms of policy as compared to conventional models: unanticipated increases in interest rates increased inflation and output while unanticipated increases in lump-sum taxes decreased inflation and output. Unanticipated shifts in monetary and fiscal policies however, played no substantial role in explaining the variation of inflation and output at any horizon in either of the time periods. Pre-Volcker, in sharp contrast to postVolcker, we find that a time-varying inflation target does not explain low-frequency movements in inflation. A combination of shocks account for the dynamics of output, inflation, and government debt, with the relative importance of a particular shock quite different in the two time-periods due to changes in the systematic responses of policy. Finally, in a counterfactual exercise, we show that had the monetary policy regime of the post-Volcker era been in place pre-Volcker, inflation volatility would have been lower by 34% and the rise of inflation in the 1970s would not have occurred. JEL codes: C52,

We study spillover effects of US uncertainty fluctuations using panel data from fifteen emerging market economies (EMEs). A US uncertainty shock negatively affects EME stock prices and exchange rates, raises EME country spreads, and leads to capital outflows from them. Moreover, it decreases EME output, while increasing their consumer prices and net exports. The negative effects on output, exchange rates, and stock prices are weaker, but the effects on capital and trade flows stronger, for South American countries compared to other EMEs. We present a model of a small open economy that faces an external shock to interpret our findings.