Sydney C. Ludvigson

Macro Factors in Bond Risk Premia

Empirical evidence suggests that excess bond returns are forecastable by financial indicators such as forward spreads and yield spreads, a violation of the expectations hypothesis based on constant risk premia. But existing evidence does not tie the forecastable variation in excess bond returns to underlying macroeconomic fundamentals, as would be expected if the forecastability were attributable to time variation in risk premia. We use the methodology of dynamic factor analysis for large datasets to investigate possible empirical linkages between forecastable variation in excess bond returns and macroeconomic fundamentals. We find that several common factors estimated from a large dataset on U.S. economic activity have important forecasting power for future excess returns on U.S. government bonds. Following Cochrane and Piazzesi (2005), we also construct single predictor state variables by forming linear combinations of either five or six estimated common factors. The single state variables forecast excess bond returns at maturities from two to five years, and do so virtually as well as an unrestricted regression model that includes each common factor as a separate predictor variable. The linear combinations we form are driven by both real and inflation macro factors, in addition to financial factors, and contain important information about one year ahead excess bond returns that is not captured by forward spreads, yield spreads, or the principal components of the yield covariance matrix.

Consumption and Credit: A Model of Time-Varying Liquidity Constraints

This paper studies the optimal consumption behavior of individuals who face borrowing limitations that vary stochastically with their income. This framework is motivated by new empirical evidence that I document in U.S. aggregate data: predictable growth in consumer credit is significantly related to consumption growth, a finding that is inconsistent with existing models of consumer behavior. The time-varying liquidity constraint model considered here correctly predicts two key properties of the U.S. aggregate data: the correlation of consumption growth with predictable credit growth documented in this paper, and the well-known correlation between consumption growth and predictable income growth that has been documented extensively elsewhere.

Time-Varying Risk Premia and the Cost of Capital: An Alternative Implication of the Q Theory of Investment

Evidence suggests that expected excess stock market returns vary over time, and that this variation is much larger than that of expected real interest rates. It follows that a large fraction of the movement in the cost of capital in standard investment models must be attributable to movements in equity risk premia. In this Paper we emphasise that such movements in equity risk premia should have implications not merely for investment today, but also for future investment over long horizons. In this case, predictive variables for excess stock returns over long-horizons are also likely to forecast long-horizon fluctuations in the growth of marginal Q, and therefore investment. We test this implication directly by performing long-horizon forecasting regressions of aggregate investment growth using a variety of predictive variables shown elsewhere to have forecasting power for excess stock market returns.

Advances in Consumption-Based Asset Pricing: Empirical Tests

The last 15 years has brought forth an explosion of research on consumption-based asset pricing as a leading contender for explaining aggregate stock market behavior. This research has propelled further interest in consumption-based asset pricing, as well as some debate. This chapter surveys the growing body of empirical work that evaluates todays leading consumption-based asset pricing theories using formal estimation, hypothesis testing, and model comparison. In addition to summarizing the findings and debate, the analysis seeks to provide an accessible description of a few key econometric methodologies for evaluating consumption-based models, with an emphasis on method-of-moments estimators. Finally, the chapter offers a prescription for future econometric work by calling for greater emphasis on methodologies that facilitate the comparison of multiple competing models, all of which are potentially misspecified, while calling for reduced emphasis on individual hypothesis tests of whether a single model is specified without error.

The Channel of Monetary Transmission to Demand: Evidence from the Market for Automobile Credit

In response to tight money, both consumer loans and consumption fall. The author asks whether there is any causality running from loans to consumption by focusing on how the composition of automobile finance between bank and nonbank sources of credit changes in response to unanticipated innovations in monetary policy. The results indicate that contractionary monetary policy produces a statistically significant reduction in the relative supply of bank consumer loans, which in turn produces a decline in real consumption. The evidence therefore supports the existence of a credit channel of monetary transmission to aggregate consumption. Moreover, the nature of automobile finance is uniquely suited to identifying which of two possible sub-channels of the broader credit channel is relatively more important, and suggests the results are more likely consistent with a bank lending channel than with a pure balance sheet channel. However, the findings also indicate that the quantitative effects of the lending channel on the aggregate economy, though precisely estimated, may be quite small.