DS-optimal designs in one way ANOVA

Characterization and construction of optimal designs using the familiar optimality criteria, for example A-, D- and E-optimality are well studied in the literature. However the study of the Distance Optimality (DS-) criterion introduced by Sinha (1970) has very recently drawn attention of researchers. In the present article, we consider the singularly estimable full rank problem of estimating the full set of elementary treatment contrasts using the DS optimality criterion in the set up of a one way ANOVA model. Using a limit argument it turns out that a CRD in which difference between any two allocation numbers is at the most unity is uniquely DS-optimal. Acknowledgement. We are thankful to Prof. B. K. Sinha for suggesting the problem to us and many helpful discussions with him. We are also thankful to the referees for drawing our attention to the reference of Bischoff (1995) and many helpful comments.     

Country size and ‘insulation’ from external disturbances

Summary This paper considers the relationship between economic size and vulnerability to external disturbances. In order to analyze this issue effectively a model comprising three different-sized economies is constructed. The issue of economic size and insulation is approached from this alternative perspectives depending upon the relative size of (a) the `recipient' country and (b) the transmitting country. The results of the analysis indicate that, contrary to popular belief, a small country under floating exchange rates is less severely affected by external economic events than a large economy regardless of the type of external disturbance and the degree of domestic wage indexation.This paper has been improved by the helpful comments of a referee. We alone are solely responsible for all remaining errors.     

Collateral constraints and the amplification mechanism

Kiyotaki and Moore (J. Polit. Economy 105 (1997) 211) have offered a theory for how common shocks to credit-constrained firms are amplified through changes in collateral values and transmitted as fluctuations in output. I clarify and extend their model by showing that their collateral amplification mechanism is not robust to the introduction of markets that allow these firms to hedge against common shocks. A theory of incomplete hedging is proposed in which the supply of hedging available in the economy is constrained by the aggregate value of collateral. I illustrate how the constraint reinstates amplification effects and discuss empirical implications of this new mechanism.     

Institutions Rule: The Primacy of Institutions Over Geography and Integration in Economic Development

We estimate the respective contributions of institutions, geography, and trade in determining income levels around the world, using recently developed instrumental variables for institutions and trade. Our results indicate that the quality of institutions trumps everything else. Once institutions are controlled for, conventional measures of geography have at best weak direct effects on incomes, although they have a strong indirect effect by influencing the quality of institutions. Similarly, once institutions are controlled for, trade is almost always insignificant, and often enters the income equation with the wrong (i.e., negative) sign. We relate our results to recent literature, and where differences exist, trace their origins to choices on samples, specification, and instrumentation.     

Can absence make a team grow stronger?

Some projects have such diverse requirements that they need a variety of specialists to work on them. But often the best-qualified specialists are scattered around the globe, perhaps at several companies. Remarkably, an extensive benchmarking study reveals, it isn't necessary to bring team members together to get their best work. In fact, they can be even more productive if they stay separated and do all their collaborating virtually. The scores of successful virtual teams the authors examined didn't have many of the psychological and practical obstacles that plagued their more traditional, face-to-face counterparts. Team members felt freer to contribute--especially outside their established areas of expertise. The fact that such groups could not assemble easily actually made their projects go faster, as people did not wait for meetings to make decisions, and individuals, in the comfort of their own offices, had full access to their files and the complementary knowledge of their local colleagues. Reaping those advantages, though, demanded shrewd management of a virtual team's work processes and social dynamics. Rather than depend on videoconferencing or e-mail, which could be unwieldy or exclusionary, successful virtual teams made extensive use of sophisticated online team rooms, where everyone could easily see the state of the work in progress, talk about the work in ongoing threaded discussions, and be reminded of decisions, rationales, and commitments. Differences were most effectively hashed out in tele-conferences, which team leaders also used to foster group identity and solidarity. When carefully managed in this way, the clash of perspectives led not to acrimony but, rather, to fundamental solutions, turning distance and diversity into competitive advantage.     

Preferential Trading and Real Wages

Following the Stolper–Samuelson type of logic, the general impression is that freeing up trade, whether preferentially as in the North American Free Trade Agreement (NAFTA) or on a nondiscriminatory basis as in the Uruguay Round, must lower real wages in one set of countries and raise them in the other set of countries. An increase in the real wage in all countries as a result of freeing up of trade either relies on gains via an improvement in the terms of trade or requires special assumptions such as increasing returns, complete specialization or asymmetries in production technology. This paper shows that even within a standard three-country, three-good, small-union model, preferential trade liberalization can lead to increased real wages in both partner countries without necessarily relying on terms-of-trade improvements, increasing returns, complete specialization, or asymmetries in production technology.     

A look at ‘overshooting’ in a two-tier float exchange rate system

This note examines the celebrated ‘overshooting’ hypothesis in the context of a two-tier float exchange rate regime. It is shown that monetary expansion leads to depreciation of both spot exchange rates and there is a presumption in favor of financial exchange rate ‘overshooting’.