The intertemporal elasticity of investment for long-lived capital goods is nearly infinite. Consequently, investment prices should fully reflect temporary tax subsidies, regardless of the investment supply elasticity. Since prices move one-for-one with the subsidy, elasticities can be inferred from quantities alone. This paper uses a recent tax policy—bonus depreciation—to estimate the investment supply elasticity. Investment in qualified capital increased sharply. The estimated elasticity is high—between 6 and 14. There is no evidence that market prices reacted to the subsidy, suggesting that adjustment costs are internal, or that measurement error masks the price changes.

We investigate well-being changes for single mother headed families targeted by recent tax and welfare reforms. Measured income changes sharply differ from consumption changes. We examine disaggregated consumption, time use, and health insurance coverage. Increases in housing and transportation spending mostly account for the rise in consumption in the bottom quintiles. We find modest improvement in housing quality, but the evidence is less strong at the very bottom. The consumption of nonmarket time for those in the bottom half of the consumption distribution falls sharply, indicating a loss in utility for those families if nonmarket time is valued above $3 per hour.

A key issue in monetary policymaking is the appropriate division of labor between the profes? sional staff of the central bank and the appointed policymakers. Lars E. O. Svensson (1999) argues that the appropriate role of a policymaking group, such as the Federal Open Market Com? mittee (FOMC) in the United States, is to make judgments about social welfare, taking as given the likely outcomes of different policies as esti? mated by the staff. In this division, the staff is relied upon to assess current and prospective economic conditions and to forecast the effects of different policies. Policymakers' only role is to decide which of the various options should be chosen.

We examine why developed societies are monogamous while rich men throughout history have typically practiced polygyny. Wealth inequality naturally produces multiple wives for rich men in a standard model of the marriage market. However, we demonstrate that higher female inequality in the marriage market reduces polygyny. Moreover, we show that female inequality increases in the process of development as women are valued more for the quality of their children than for the quantity. Consequently, male inequality generates inequality in the number of wives per man in traditional societies, but manifests itself as inequality in the quality of wives in developed societies.

Based on recent neuroscience evidence, we model the brain as a dual-system organization subject to three conflicts: asymmetric information, temporal horizon, and incentive salience. Under the first and second conflicts, we show that the uninformed system imposes a positive link between consumption and labor at every period. Furthermore, decreasing impatience endogenously emerges as a consequence of these two conflicts. Under the first and third conflicts, it becomes optimal to set a consumption cap. Finally, we discuss the behavioral implications of these rules for choice bracketing and expense tracking, and for consumption over the life cycle.

Economics has traditionally relied on revealed preferences (and, occasionally, on verbal reports) to understand the desires of people. Another source of information has been developed in recent years: the direct observation of choice processes. This mechanism, possible thanks to the improvements in the designs and techniques to measure brain activity, is explored in the bur geoning field of experimental neuroeconom ics (see Paul W. Glimcher and Aldo Rustichini (2004) and Colin Camerer, George Loewenstein, and Drazen Prelec (2005) for recent surveys). In this article, we argue that the evidence on brain activity can also be used to build theo retical models that help us understand choices and predict behaviors. We label this research “Neuroeconomic Theory.” In Section I, we describe the procedure, discuss some advan tages over traditional methodologies, and estab lish some facts that motivate our approach. In Section II, we illustrate the methodology with two brain-based models of decision making. I. What is “Neuroeconomic Theory”? Neuroeconomic theory is an interdisciplin ary line of investigation that combines research from neuroscience, neurobiology, and econom ics. Experimental neuroscience and neurobiology provide detailed evidence of the functionality, interconnectivity, and physiological constraints of the brain systems involved in decision making. Microeconomic theory supplies the toolkit to build simple optimization models that incorporate these network interactions and well-defined con straints into the mechanisms of choice.

Allowing the Data to Speak Freely: The Macroeconometrics of the Cointegrated Vector Autoregression by Kevin D. Hoover, Soren Johansen and Katarina Juselius. Published in volume 98, issue 2, pages 251-55 of American Economic Review, May 2008

Exploring the Impact of Financial Incentives on Stereotype Threat: Evidence from a Pilot Study by Roland G. Fryer Jr., Steven D. Levitt and John A. List. Published in volume 98, issue 2, pages 370-75 of American Economic Review, May 2008