Current Working Papers

1. Internal versus External Habits: Why Does the Distribution of Stock Returns have ARCH Properties?.
Written with Yu Chen and Alex Himonas.

    Abstract:  We develop an explicit formula for the distribution of U.S. returns that explains many of its observed  characteristics: excess kurtosis, volatility clustering, leverage effects, volatility feedback, and the equity premium. Researchers have often made the assumption of ARCH distributions to capture these characteristics; ARCH models were developed expressly for this purpose. The most important contribution of this paper is that our model  depends on fundamental factors, cash flows and   investor preferences, to explain these characteristics, rather than depending on an assumed distribution of returns. Our solution also explains about 66% of  the rise in returns volatility during the Depression.
View paper .pdf

2. By Force of Habit: An Exploration of Asset Pricing Models using Analytic Methods.
Written with Yu Chen and Alex Himonas.

    Abstract: Complex analysis is used to explore a new solution method for asset pricing models. Campbell and Cochrane's (1999) habit persistence model provides a prototypical example to illustrate these methods. Using complex analysis  we are able to find the maximum radius of convergence so that the price-dividend function can be expressed as a Taylor series for any consumption growth within  [-8, 8] standard deviations per month. While the numerical method used by Campbell and Cochrane does not provide an accurate approximation, moderate adjustment in their parameters recover their general implications. Finally, the distribution of stock returns mimics the kurtosis and time varying risk premium found in monthly data.View paper .pdf

3. Solving Ramsey Problems with Nonlinear Projection Methods. Forthcoming Studies in Nonlinear Dynamics & Econometrics, Vol. 9, Spring 2005.
Written with Mike Gapen.
    Abstract: This paper examines the usefulness of nonlinear projection methods in solving Ramsey problems by investigating welfare enhancing properties of debt through policy smoothing. The presence of nonlinear distortions in the Ramsey problem requires the use of a solution procedure which captures these effects. The nonlinear projection method, even with low-order Chebyshev polynomials as employed in this paper, is able to capture a significant portion of the Jensen's inequality effects. In an explicit monetary economy we examine Barro's (1987, 1979) conjecture that welfare gains are available from policy smoothing with debt. Increases in
the volatility of distortionary monetary policy are more than offset by declines in the volatility of distortionary labor taxes so that introduction of debt is welfare enhancing..View paper .pdf

4. Optimal Fiscal and Monetary Policy with Nominal and Indexed Debt.
Written with Mike Gapen.
    Abstract: This paper focuses on the importance of debt composition in the setting of optimal fiscal and monetary policy over both short-run business cycles and
the long-run. The main conclusion is that nominal debt as state-contingent debt can be a significant policy tool to reduce volatility of distortionary government policy, thereby reducing macroeconomic volatility while increasing equilibrium output and consumption. The gain in welfare from using nominal debt to hedge against shocks to the government budget is equivalent to a .6% increase in consumption growth for the United States which is  nearly as large as the gain in welfare from the ability to issue debt. In addition the gain in welfare for a country with twice the U.S. debt is similar to a 2% increase in consumption growth.View paper .pdf

5. Solving Asset Pricing Models  when the Price-Dividend Function is Analytic. Including unpublished Appendix. Forthcoming Econometrica.
Written with Ovidiu Calin, Yu Chen and Alex Himonas. .View paper .pdf
Solving Asset Pricing Models  when the Price-Dividend Function is Analytic (Longer Version).
Written with Stefano Athanasoulis, Ovidiu Calin and Alex Himonas
    Abstract: We present a new method for solving asset pricing models, which yields an analytic price-dividend function of one state variable. To illustrate our method we give a detailed analysis of Abel's asset pricing model (see Theorem 1).  A function is analytic in an open interval if it can be represented as a convergent power series  near every point of that interval. In addition to allowing us to solve for the exact equilibrium price-dividend function, the analyticity property also lets us assess the accuracy of any numerical solution procedure used in the asset pricing literature.
Mathematica Programs for Solving Asset Pricing Models  when the Price-Dividend Function is Analytic.

6. OPTIMAL EXPERIMENTATION AND THE PERTURBATION METHOD IN THE NEIGHBORHOOD OF THE AUGMENTED LINEAR REGULATOR PROBLEM.
       Abstract: The perturbation method is used to approximate optimal experimentation problems. The approximation is in the neighborhood of the linear regulator problem which has a well-defined solution procedure. The first order perturbation of the optimal decision under experimentation is a combination of the linear regulator solution and a term that captures the impact of the uncertainty on the agent's value function. An algorithm is developed to quickly implement this procedure on the computer. As a result, the impact of optimal experimentation on an agent's decisions can be quantified and estimated for a large class of problems encountered in economics.
  

7. MONETARY POLICY WITH A TOUCH OF BASEL(Previous title "The Conduct of Monetary Policy under the Basel Accord")
Written with Ralph Chami
    Abstract
: Monetary policy impacts banks under the Basel Accord through its influence on the net interest margin between loan and deposit rates. The net interest margin is above the marginal cost of loans because of anti-competitive pricing by banks. If the central bank raises the treasury rate, there is a corresponding change in the deposit rate both this quarter and in the future, which leads to an increase in the marginal cost of loans. The higher marginal cost of loans results in the  bank setting a smaller net interest margin which reduces loans and profits. In anticipation of a reduction in the use of total capital in the future, the bank chooses to reduce total capital. The lower total capital implies that the bank is less likely to meet unanticipated increases in loan demand in the future. Thus, contractionary monetary policy under the Basel Accord acts through its restriction on bank's total capital.(View paper .pdf)
 

8. DISCRETIONARY DISCLOSURES OVER TIME
Written with Bjorn Jorgensen and Ram Ramanan

       Abstract: We formulate the multi-period problem of discretionary disclosures of the value relevant component of earnings when disclosure of earnings is mandatory. We establish that there only exists partial disclosure equilibrium characterized by a disclosure threshold, such that discretionary disclosures arise if and only if the information is above the threshold.  This disclosure threshold is increasing in the mean and decreasing in the variance of earnings.  Further, the threshold can either increase or decrease over time.

Recent Publications

1. CAPITAL TRADING, STOCK TRADING, AND THE INFLATION TAX ON EQUITY
Written with Ralph Chami and Connel Fullenkamp
Review of Economic Dynamics, July 2001
NOTE: Review of Economic Dynamics, October 2003
Written with Scott Baier, Charles Carlstrom, Ralph Chami, Timothy Fuerst, and Connel Fullenkamp.
    Abstract:  A market for used capital goods, or financial instruments that represent the ownership of th used capital goods, induces inflation taxes on wealth and on the norminal income flows they provide.  This paper explicity introduces trading in either used capital goods or financial instruments into the standard stochastic growth model with money and production.  These two monetary economies are equivalent.  The value of the firm is equal to the firm's capital stock divided by inflation.  The resulting asset-pricing conditions indicate that the effect of inflation on asset returns differs from the effects found in the literature by the addition of a significant wealth tax. (View  paper .pdf)

2. Financial Institutions and Trustworthy Behavior in Business Transactions Journal of Business Ethics 52(2), (2004) 179-188.
     Abstract: This paper uses the bankruptcy proceedings for Enron to discuss the role of financial institutions in business transactions. Using recent work by Dixit a business transaction is portrayed as a prisoners’ dilemma problem between competing firms. The financial institution’s role in this world is to provide information and enforce contracts so that the parties to the business deal act cooperatively. This role is recognized in the law under the heading of Fiduciary Responsibility. In the Enron case the bankruptcy examiner has argued that the Tier 1 financial institutions for Enron failed to carry out their fiduciary responsibility. As a result, the examiner has asked a fact finder to subordinate the claims of the Tier 1 financial institutions to other debt holders for Enron.(View paper .pdf)