Neo Wang

This article examines the quantitative interrelations between sectoral composition of public spending and equilibrium determinacy in a two-sector real business cycle model with positive productive externalities in investment. When government purchases of consumption and investment goods are set as constant fractions of their respective sectoral output, we show that the public-consumption share plays no role in the model's local dynamics, and that a sufficiently high public-investment share can stabilize the economy against endogenous belief-driven cyclical fluctuations. When each type of government spending is postulated as a constant proportion of the economy's total output, we find that there exists a trade-off between public consumption versus investment expenditures to yield saddle-path stability and equilibrium uniqueness. © 2014 Western Economic Association International.

© Copyright 1999 by the American Geophysical Union.We have measured emissions of CH3C1, CH3Br, and 2S from Holstein cows. In one experiment, two cows were studied in separate metabolic research chambers for a 24-hour period while on a normal diet and were studied for an additional 24-hour period 1 week later after being placed on a diet enhanced in chloride and bromide. Methyl chloride emissions ranged between 0.4 × 10-3 and 1.5 × 10-3 g cow-1 d-1, while methyl bromide emissions were much smaller, 3 × 10-6-2 × 10∼5 g cow-1 d-1. Daily emissions of methane from these cows were 134-180 g cow-1 d-1, quite similar to values found in many previous studies. A second 24-hour study of two different cows on normal diets yielded daily emissions of 0.6 × 10-3 and 0.9 × 10-3 g CH3C1, 0-1.0 × 10-6 g CH3Br, and 191 and 176 g CH4. If these emissions of CH3C1 and CH3Br are representative of the 1.3 billion head of cattle worldwide, then the global source of atmospheric CH3C1 and CH3Br from cattle would be 0.23-0.70 Gg yr-1 and × 10-3 Gg yr-1, respectively. These emissions of CH3C1 and CH3Br represent <0.02% and <0.005%, respectively, of the total annual global atmospheric sources of these compounds; therefore, emissions of CH3C1 and CH3Br from cattle are insignificant contributors to their total sources. Discovered serendipitously, DMS emissions were between 0.17 and 0.24 g cow-1 d-1, and chloroform emissions were 2 × 10-4-3 × 10-3 g cow-1 d-1. DMS from cattle is not a major source over hemispheric or global scales but could be important in certain geographical regions. Chloroform emissions were similarly detected and quantified, as were those of C2H5X.