Testing the purchasing power parity in panel data

This paper empirically tests the purchasing power parity (PPP) using panel unit root tests. We employ a battery of panel unit root tests: LM-bar statistic [Testing for unit roots in heterogeneous panels, Working paper, University of Cambridge] is employed to account for serially correlated errors. The statistic proposed by Breitung [Adv. Econom. 15 (2000) 161.] and the KPSS-based statistic of Hadri [Econ. J. 3 (2000) 148.] are also used. In addition, we also employ a SUR estimator to account for possible cross-sectional effect. Data of 45 economies from 1980 to 1999 are used to test the PPP hypothesis. We find that these estimators tend to get supportive results when the data frequency becomes lower, which substantially characterizes the long-run property of the PPP hypothesis.     

Quantity versus variety: Which aspect does status-seeking promote?

We introduce status goods in a model of monopolistic competition for investigating whether a stronger preference for status promotes a higher quantity or a greater variety of status goods in equilibrium. We argue that diversification is a more likely outcome. Elasticity of marginal status is identified as the crucial factor. Under the widely adopted relative-consumption hypothesis, elasticity of marginal status equals one, which supports a higher variety. Under other hypotheses, if the status return from an extra unit of own consumption falls as others’ consumption rises, elasticity of marginal status is likely to be higher than one or not substantially smaller than one. In these reasonable patterns, diversification also tends to appear.     

On relative and partial risk attitudes: theory and implications

This paper develops context-free interpretations for the relative and partial Nth degree risk attitude measures and show that various conditions on theses measures are utility characterizations of the effects of scaling general stochastic changes in different settings. It is then shown that these characterizations can be applied to generalize comparative statics results in a number of important problems, including precautionary savings, optimal portfolio choice, and competitive firms under price uncertainty.     

INNOVATION AND GROWTH WITH FINANCIAL,AND OTHER,FRICTIONS

The generation of ideas and their implementation are crucial for economic performance. We study this in a model of endogenous growth, where productivity increases with innovation and where the exchange of ideas (technology transfer) allows those with comparative advantage to implement them. Search, bargaining, and commitment frictions impede the idea market, however, reducing efficiency and growth. We characterize optimal policies involving subsidies to innovative and entrepreneurial activity, given both knowledge and search externalities. The role of liquidity is discussed. We show intermediation helps by financing more transactions with fewer assets and, more subtly, by ameliorating holdup problems. We also discuss some evidence.     

The U.S. trade imbalance and real exchange rate: An application of the heterogeneous panel cointegration method

The United States economy suffers from persistent trade deficits, arising from the so-called ‘global external imbalance’. Can the depreciation of the US dollar improve this phenomenon? This study for the first time applies the heterogeneous panel cointegration method to examine the long-run relationship between the real exchange rate and bilateral trade balance of the U.S. and her 97 trading partners for the period 1973–2006. Using new annual data, the empirical results indicate that the devaluation of the US dollar deteriorates her bilateral trade balance with 13 trading partners, but improves it with 37 trading partners, especially for China. In the panel cointegrated framework, a long-run negative relationship between the real exchange rate and the bilateral trade balance exists for the U.S.