Anna Pavlova

The Role of Portfolio Constraints in the International Propagation of Shocks

We study the comovement among stock prices and exchange rates in a three-good, three-country, Centre-Periphery, dynamic equilibrium model in which the Centres agents face portfolio constraints. We characterize equilibrium in closed form for a broad class of portfolio constraints, solving for stock prices, terms of trade, and portfolio holdings. We show that portfolio constraints generate wealth transfers between the Periphery countries and the Centre, which increase the comovement of the stock prices across the Periphery. We associate this excess comovement caused by portfolio constraints with the phenomenon known as contagion. The model generates predictions consistent with other important empirical results such as amplification and flight-to-quality effects. Copyright 2008, Wiley-Blackwell.

Asset Prices and Institutional Investors

Empirical evidence indicates that trades by institutional investors have sizable effects on asset prices, generating phenomena such as index effects, asset-class effects and others. It is difficult to explain such phenomena within standard representative-agent asset pricing models. In this paper, we consider an economy populated by institutional investors alongside standard retail investors. Institutions care about their performance relative to a certain index. Our framework is tractable, admitting exact closed-form expressions, and produces the following analytical results. We find that institutions optimally tilt their portfolios towards stocks that comprise their benchmark index. The resulting price pressure boosts index stocks, while leaving nonindex stocks unaffected. By demanding a higher fraction of risky stocks than retail investors, institutions amplify the index stock volatilities and aggregate stock market volatility, and give rise to countercyclical Sharpe ratios. Trades by institutions induce excess correlations among stocks that belong to their benchmark index, generating an asset-class effect.

A Model of Financialization of Commodities

A sharp increase in the popularity of commodity investing in the past decade has triggered an unprecedented inflow of institutional funds into commodity futures markets, referred to as the financialization of commodities. In this paper, we explore the effects of financialization in a model that features institutional investors alongside traditional futures markets participants. The institutional investors care about their performance relative to a commodity index. We find that in the presence of institutional investors prices and volatilities of all commodity futures go up, but more so for the index futures than for nonindex ones. The correlations amongst commodity futures as well as in equity-commodity correlations also increase, with higher increases for index commodities. Within a framework additionally incorporating storage, we show how financial markets transmit shocks not only to futures prices but also to commodity spot prices and inventories. Commodity spot prices and inventories go up with financialization. In the presence of institutional investors shocks to any index commodity spill over to all storable commodity prices.

Equilibrium Portfolios and External Adjustment under Incomplete Markets

Recent evidence on the importance of cross-border equity flows calls for a rethinking of the standard theory of external adjustment. We introduce equity holdings and portfolio choice into an otherwise conventional open-economy dynamic equilibrium model. Our model is simple and it admits an exact closed-form solution regardless of whether financial markets are complete or incomplete. We derive a necessary and sufficient condition under which the current account is different from zero and shed light on the relationship between market incompleteness and the current account dynamics. Furthermore, we revisit the current debate on the relative importance of the standard vs. the capital-gains-based (or “valuation”) channels of the external adjustment and establish that in our framework they are congruent. We demonstrate how countries’ portfolio compositions affect the dynamics of their external accounts and argue that a description of the international adjustment mechanism is incomplete if it does not encompass portfolio choice.

International Macro-Finance

International macro-finance is a new area of open economy macroeconomics that brings portfolio choice and asset pricing considerations into models of international macroeconomics. The importance of these considerations--typically relegated to Finance and largely overlooked in traditional macroeconomics--for the international macroeconomy have been underscored by a series of recent financial crises and by unprecedented global imbalances. In this paper, we survey recent developments in this area, primarily on the theoretical front. We also suggest several promising directions for future research.

Multiplicity in General Financial Equilibrium with Portfolio Constraints

This paper explores the role of portfolio constraints in generating multiplicity of equilibrium. We present a simple financial market economy with two goods and two households, households who face constraints on their ability to take unbounded positions in risky stocks. Absent such constraints, equilibrium allocation is unique and is Pareto efficient. With one portfolio constraint in place, the efficient equilibrium is still possible; however, additional inefficient equilibria in which the constraint is binding may emerge. We show further that with portfolio constraints cum incomplete markets, there may be a continuum of equilibria; adding incomplete markets may lead to real indeterminacy.

Adjustment Costs, Learning-by-Doing, and Technology Adoption Under Uncertainty

We consider a variety of vintage capital models of a firm?s choice of technology under uncertainty in the presence of adjustment costs and technology-specific learning. Similar models have been studied in a deterministic setting. Part of our objective is to examine the robustness of the implications of the certainty models to uncertainty. We find that the answer crucially depends on the specification of the costs of adoption of a new vintage of technology. In particular, if the cost comes only in terms of accumulated technology-specific expertise (cf. Parente (1994)), we demonstrate that the implications are robust for a variety of specifications of the firm?s production function. However, once we develop a model in which each adoption requires a capital expenditure, predictions become increasingly di?erent as uncertainty increases. The model implies that in booms, the firm accelerates adoptions of new technologies, delaying them in recessions. Adverse e?ects of a recession on the investment decisions are alleviated in part by the firm?s expertise (or human capital). Compared to the deterministic benchmark, the firm increases the pace of adoptions, making a smaller technological advance each time it upgrades its technology. Overall, uncertainty negatively impacts growth and the firm value.

A Dynamic Model with Import Quota Constraints

This Paper develops a continuous-time two-sector model to study the economic effects of an import quota during the period of time over which it is imposed. One of the sectors is protected by a quota, which in our set-up manifests itself as an integral constraint on the flow of imports of the protected commodity. In sharp contrast to the existing literature, our small open economy exhibits distinctly different economic behaviour depending on whether the country is importing the protected good, exporting it or refraining from trade in it. The domestic price of the protected good exceeds the world price in import and no-trade regions, even when the quota is underutilized - in contrast, existing work predicts no economic effects of a quota unless it is binding. Within a general equilibrium world economy consisting of one quota-constrained and one unconstrained country, under logarithmic preferences, the constrained country becomes wealthier at the expense of the unconstrained. Moreover, the stock price of the protected industry increases in the quota-constrained and decreases in the unconstrained country