The "Great Moderation" and the US External Imbalance

The early 1980s marked the onset of two striking features of the current world macro-economy: the fall in US business cycle volatility (the "great moderation") and the large and persistent US external imbalance. In this paper we argue that an external imbalance is a natural consequence of the great moderation. If a country experiences a fall in volatility greater than that of its partners, its relative incentives to accumulate precautionary savings fall and this results in an equilibrium permanent deterioration of its external balance. To assess how much of the current US imbalance can be explained by this channel, we consider a standard two country business cycle model in which households are subject to country specific shocks they cannot perfectly insure against. The model suggests that a fall in business cycle volatility like the one observed for the US relatively to other major economies can account for about 20% of the current total US external imbalance.

International recessions

The 2007–2009 crisis was characterized by an unprecedented degree of international synchronization as all major industrialized countries experienced large macroeconomic contractions around the date of Lehman bankruptcy. At the same time countries also experienced large and synchronized tightening of credit conditions. We present a two-country model with financial market frictions where a credit tightening can emerge as a self-fulfilling equilibrium caused by pessimistic but fully rational expectations. As a result of the credit tightening, countries experience large and endogenously synchronized declines in asset prices and economic activity (international recessions). The model suggests that these recessions are more severe if they happen after a prolonged period of credit expansion.

The international diversification puzzle is not as bad as you think

In simple one-good international macro models, the presence of non-diversifiable labor income risk means that country portfolios should be heavily biased toward foreign assets. The fact that the opposite pattern of diversification is observed empirically constitutes the international diversification puzzle. We embed a portfolio choice decision in a frictionless two-country, two-good version of the stochastic growth model. In this environment, which is a workhorse for international business cycle research, we derive a closed-form expression for equilibrium country portfolios. These are biased towards domestic assets, as in the data. Home bias arises because endogenous international relative price fluctuations make domestic stocks a good hedge against non-diversifiable labor income risk. We then use our theory to link openness to trade to the level of diversification, and find that it offers a quantitatively compelling account for the patterns of international diversification observed across developed economies in recent years.Investments, Foreign ; International trade - Econometric models

Financial Globalization and Real Regionalization

Over the period 1972-1986, the correlations of GDP, employment and investment between the United States and an aggregate of Europe, Canada and Japan were respectively 0.76, 0.66, and 0.63. For the period 1986 to 2000 the same correlations were much lower: 0.26, 0.03 and -0.07 (real regionalization). At the same time, U.S. international asset trade has significantly increased. For example, between 1972 and 1999, United States gross FDI and equity assets in the same group of countries rose from 4 to 23 percent of the U.S. capital stock (financial globalization). We document that the correlation of real shocks between the U.S. and the rest of the world has declined. We then present a model in which international financial market integration occurs endogenously in response to less correlated shocks. Financial integration further reduces the international correlations in GDP and factor supplies. We find that both less correlated shocks and endogenous financial market development are needed to account for all the changes in the international business cycle.

Does income inequality lead to consumption equality? evidence and theory

Using data from the Consumer Expenditure Survey, we first document that the recent increase in income inequality in the United States has not been accompanied by a corresponding rise in consumption inequality. Much of this divergence is due to different trends in within-group inequality, which has increased significantly for income but little for consumption. We then develop a simple framework that allows us to analytically characterize how within-group income inequality affects consumption inequality in a world in which agents can trade a full set of contingent consumption claims, subject to endogenous constraints emanating from the limited enforcement of intertemporal contracts (as in Kehoe and Levine, 1993). Finally, we quantitatively evaluate, in the context of a calibrated general equilibrium production economy, whether this setup, or alternatively a standard incomplete markets model (as in Aiyagari, 1994), can account for the documented stylized consumption inequality facts from the U.S. data.Income distribution ; Consumption (Economics)

Does Income Inequality Lead to Consumption Inequality? Evidence and Theory

Using data from the Consumer Expenditure Survey we first document that the recent increase in income inequality in the US has not been accompanied by a corresponding rise in consumption inequality. Much of this divergence is due to different trends in within-group inequality, which has increased significantly for income but little for consumption. We then develop a simple framework that allows us to analytically characterize how within-group income inequality affects consumption inequality in a world in which agents can trade a full set of contingent consumption claims, subject to endogenous constraints emanating from the limited enforcement of intertemporal contracts (as in Kehoe and Levine, 1993). Finally, we quantitatively evaluate, in the context of a calibrated general equilibrium production economy, whether this set-up, or alternatively a standard incomplete markets model (as in Ayiagari 1994), can account for the documented stylized consumption inequality facts from the US data.Limited Enforcement, Risk Sharing, Consumption Inequality

Risk sharing: private insurance markets or redistributive taxes?

We explore the welfare consequences of different taxation schemes in an economy where agents are debt-constrained. If agents default on their debt, they are banned from future credit markets, but retain their private endowments which are subject to income taxation. A change in the tax system changes the severity of punishment from default and, hence, leads to a limitation of possible risk sharing via private contracts. The welfare consequences of a change in the tax system depend on the relative magnitudes of increased risk sharing forced by the new tax system and the reduced risk sharing in private insurance markets. We quantitatively address this issue by calibrating an artificial economy to US income and tax data. We show that for a plausible selection of the structural parameters of our model, the change to a more redistributive tax system leads to less risk sharing among individuals and lower ex-ante welfare.Taxation ; Tax reform

Does Income Inequality Lead to Consumption Inequality? Evidence and Theory

This paper first documents the evolution of the cross-sectional income and consumption distribution in the US in the past 25 years. Using data from the Consumer Expenditure Survey we find that a rising income inequality has not been accompanied by a corresponding rise in consumption inequality. Over the period from 1972 to 1998 the standard deviation of the log of after-tax labor income has increased by 20% while the standard deviation of log consumption has increased less than 2%. Furthermore income inequality has increased both between and within education groups while consumption inequality has increased between education groups but mildly declined within groups. We then argue that these empirical findings are consistent with the hypothesis that an increase in income volatility has been an important cause of the increase in income inequality, but at the same time has lead to an endogenous development of credit markets, allowing households to better smooth their consumption against idiosyncratic income fluctuations. We develop a consumption model in which the sharing of income risk is limited by imperfect enforcement of credit contracts and in which the development of financial markets depends on the volatility of the individual income process. This model is shown to be quantitatively consistent with the joint evolution of income and consumption inequality in US, while other commonly used consumption models are not.

The International Diversification Puzzle Is Not as Bad as You Think

In simple one-good international macro models, the presence of non-diversifiable labor income risk means that country portfolios should be heavily biased toward foreign assets. The fact that the opposite pattern of diversification is observed empirically constitutes the international diversification puzzle. We embed a portfolio choice decision in a frictionless two-country, twogood version of the stochastic growth model. In this environment, which is a workhorse for international business cycle research, we derive a closed-form expression for equilibrium country portfolios. These are biased towards domestic assets, as in the data. Home bias arises because endogenous international relative price fluctuations make domestic stocks a good hedge against non-diversifiable labor income risk. We then use our our theory to link openness to trade to the level of diversification, and find that it offers a quantitatively compelling account for the patterns of international diversification observed across developed economies in recent years.Home bias, international diversification