Knowledge that Transforms

In this paper, we consider non-parametric identification and estimation of truncated regression models in both cross-sectional and panel data settings. For the cross-sectional case, Lewbel and Linton (2002) considered non-parametric identification and estimation through continuous variation under a log-concavity condition on the error distribution. We obtain non-parametric identification under weaker conditions. In particular, we obtain non-parametric identification through discrete variation under a non-periodicity condition on the hazard function of the error distribution. Furthermore, we show that the presence of continuous regressors may lead to stronger identification results. Our non-parametric estimator is shown to be consistent and asymptotically normal, and outperforms that of Lewbel and Linton (2002) in a simulation study. For the panel data setting, we provide the first systematic treatment of non-parametric identification and estimation of the truncated panel data model with fixed effects by extending our treatment of the cross-sectional case. We also consider various other extensions.

Under mild assumptions, the data indicate that fluctuations in nominal interest rate differentials across currencies are primarily fluctuations in time-varying risk. This finding is an immediate implication of the fact that exchange rates are roughly random walks. If most fluctuations in interest differentials are thought to be driven by monetary policy, then the data call for a theory which explains how changes in monetary policy change risk. Here, we propose such a theory based on a general equilibrium monetary model with an endogenous source of risk variation—a variable degree of asset market segmentation.

This paper introduces a new class of parameter estimators for dynamic models, called simulated non-parametric estimators (SNEs). The SNE minimizes appropriate distances between non-parametric conditional (or joint) densities estimated from sample data and non-parametric conditional (or joint) densities estimated from data simulated out of the model of interest. Sample data and model-simulated data are smoothed with the same kernel, which considerably simplifies bandwidth selection for the purpose of implementing the estimator. Furthermore, the SNE displays the same asymptotic efficiency properties as the maximum-likelihood estimator as soon as the model is Markov in the observable variables. The methods introduced in this paper are fairly simple to implement, and possess finite sample properties that are well approximated by the asymptotic theory. We illustrate these features within typical estimation problems that arise in financial economics.

We show how the willingness-to-pay problem and lack of exclusivity in sovereign lending may result in an equilibrium sovereign debt structure that is excessively difficult to restructure. A bankruptcy regime for sovereigns can alleviate this inefficiency but only if it is endowed with far-reaching powers to enforce seniority and subordination clauses in debt contracts. A bankruptcy regime that makes sovereign debt easier to restructure without enforcing seniority may decrease welfare. Copyright Copyright © 2009 The Review of Economic Studies Limited.

In this paper, I provide a theoretical explanation for the gender differences in education and on the labour market that are observed empirically in most OECD (Organisation for Economic Cooperation and Development) countries, including the US Within a cheap talk model of grading, I show that biased grading in schools results in (1) boys outperforming girls in maths and sciences, (2) boys having more top and more bottom achievers in maths and sciences than girls, (3) girls outperforming boys in reading literacy, (4) female graduates enrolling in university studies more often than male graduates, (5) the predominance of female students in arts and humanities at the university, (6) the predominance of male students in maths and sciences at the university and (7) the gender wage gap on the labour market for the highly educated.

We present a new model of multi-product firms (MPFs) and flexible manufacturing, and explore its implications in partial and general oligopolistic equilibrium. Globalization affects the scale and scope (or intensive margin and intra-firm extensive margin) of MPFs through a competition effect and a demand effect. The model highlights a new source of gains from trade: productivity increases as firms become “leaner and meaner”, concentrating on their core competence; but also a new source of losses from trade: product variety may fall. Our results also hold under free entry, which allows in addition for adjustment along the traditional inter-firm extensive margin.

Political dynasties have long been present in democracies, raising concerns that inequality in the distribution of political power may reflect imperfections in democratic representation. However, the persistence of political elites may simply reflect differences in ability or political vocation across families and not their entrenchment in power. We show that dynastic prevalence in the Congress of the U.S. is high compared to that in other occupations and that political dynasties do not merely reflect permanent differences in family characteristics. On the contrary, using two instrumental variable techniques we find that political power is self-perpetuating: legislators who hold power for longer become more likely to have relatives entering Congress in the future. Thus, in politics, power begets power.

This paper studies a mechanism design model of financial intermediation. There are two informational frictions: agents receive unobservable shocks and can participate in markets by engaging in trades unobservable to intermediaries. Without regulations, intermediaries provide no risk sharing because of an externality arising from arbitrage opportunities. We identify a simple regulation --a liquidity requirement --that corrects such an externality by affecting the interest rate on the markets. We characterize the form of the optimal liquidity adequacy requirement for a general class of preferences. We show that whether markets underprovide or overprovide liquidity, and whether a liquidity cap or a liquidity floor should be used depends on the nature of the shocks that agents experience. Moreover, we prove that the optimal liquidity adequacy requirement implements a constrained efficient allocation subject to unobservable types and trades. We provide closed form solutions for the optimal liquidity requirement and welfare gains of imposing such requirements for two important special cases. In contrast with the existing literature, the necessity of regulation does not depend on exogenous incompleteness of markets for aggregate shocks.

A number of assets do not trade publicly but are sold to a restricted group of investors who subsequently receive private information from the issuers. Thus, the holders of such privately placed assets learn more quickly about their assets than other agents. This paper studies the pricing implications of this “learning by holding”. In an economy in which investors are price takers and risk-neutral, and absent any insider trading or other transaction costs, we show that risky assets command an excess expected return over safe assets in the presence of learning by holding. This is reminiscent of the “credit spread puzzle”—the large spread between BBB-rated and AAA-rated corporate bonds that is not explained by historical defaults, risk aversion, or trading frictions. The intuition is that the seller of a risky bond needs to offer a “coordination premium” that helps potential buyers overcome their fear of future illiquidity. Absent this premium, this fear could become self-justified in the presence of learning by holding because a future lemons problem deters current market participation, and this in turn vindicates the fear of a future lemons problem

We propose a model of costly decision making based on time-costs of deliberating current and future decisions. We model an individual decision-maker's thinking process as a thought-experiment that takes time, and lets the decision maker ‘think ahead’ about future decision problems in yet unrealized states of nature. By formulating an intertemporal, state-contingent, planning problem which may involve costly deliberation in every state of nature, and by letting the decision maker deliberate ahead of the realization of a state, we attempt to capture the basic observation that individuals generally do not think through a complete action plan. Instead, individuals prioritize their thinking and leave deliberations on less important decisions to the time or event when they arise.