The Role of External Economies in U.S. Manufacturing

This paper develops a method for joint estimation of both the degree of internal returns to scale and the extent of external economies. We apply the method in estimating returns to scale indexes for U.S. manufacturing industries at the two-digit level. Overall, we find that only three of the twenty industry categories show any evidence of internal increasing returns: (1) Primary Metals, (2) Electrical Machinery, and (3) Paper Products. More striking, however, is the very strong evidence of the existence of external economies, where external is defined as external to a given two-digit industry and internal to the U.S.. According to our preferred estimates, if all manufacturing industries simultaneously raise their inputs by 10%, aggregate manufacturing production rises by 13%, of which about 5% is due to external economies. Thus, when an industry increases its inputs in isolation by 10%, its output rises by no more than 8%.

Fixed versus Flexible: Lessons from EMS Order Flow

This paper addresses the puzzle of regime-dependent volatility in foreign exchange. We extend the literature in two ways. First, our microstructural model provides a qualitatively new explanation for the puzzle. Second, we test implications of our model using Europe's recent shift to rigidly fixed rates (EMS to EMU). In the model, shocks to order flow induce volatility under flexible rates because they have portfolio-balance effects on price, whereas under fixed rates the same shocks do not have portfolio-balance effects. These effects arise in one regime and not the other because the elasticity of speculative demand for foreign exchange is (endogenously) regime-dependent: low elasticity under flexible rates magnifies portfolio-balance effects; under credibly fixed rates, elasticity of speculative demand is infinite, eliminating portfolio-balance effects. New data on FF/DM transactions show that order flow had persistent effects on the exchange rate before EMU parities were announced. After announcement, determination of the FF/DM rate was decoupled from order flow, as predicted by the model.

Ground Beetles (Coleoptera: Carabidae) Inhabiting Stands of Reed Canary Grass Phalaris Arundinacea on Islands in the Lower Chippewa River, Wisconsin

We used pitfall traps to assess ground beetle diversity (Coleoptera:Carabidae) on two islands in the lower Chippewa River, Eau Claire County, Wisconsin, with rapidly expanding populations of reed canary grass, Phalaris arundinaceae. We collected 233 individuals belonging to 17 species over four, 3-9 day sampling periods, May-August 1994. All species have been documented in Wisconsin and most are considered habitat generalists. Agonum fidele, A. extensicolle, Anisodactylus harrisii and Bembidion quadrimaculatum oppositum comprised 70% of all species collected. Seven species were common to both islands, with 13 species collected on Canarygrass Island and 11 species on Ski Jump Island. Carabid species diversity (Shannon’s H=2.01) was greatest on Canarygrass Island

STS-1 operational flight profile. Volume 5: Descent, cycle 3

The trajectory data presented are to be used for orbiter systems and subsystems evalation, flight and mission control center software verification, flight techniques and timeline development, crew training, and evaluation of operational mission suitability. The entry profile is very similar to cycle 2, however, elevon and body flap temperature margins have increased and the elevon schedule was changed. The terminal area energy management (TAEM) profile was completely reshaped to conform with new angle of attack constraints and left hand turn around the heading alignment cylinder. Also, the entry/TAEM interface was adjusted to minimize guidance induced angle of attack transients across the interface. The approach and landing phase was reshaped for a 20 deg glideslope and reduced velocity at touchdown. The definition of the runway threshold was standardized for all landing sites. This results in a shift at Edwards Air Force Base in aim points and touchdown relative to the threshold of 1000 feet. The rollout remains essentially unchanged with the exception of the speedbrake, which is now deployed to 50 percent at touchdown