The authors build a model of child labor and study its implication for welfare and fertility. Assuming there is a trade-off between child labor and human capital accumulation, we derive conditions under which child labor is socially inefficient. Even if parents are altruistic, child labor may...

The autors study the implications of the trade-off between child quality and child quantity for the efficiency of the rate of population growth. They show that if quantity and quality are inversely related then, even in the case of full altruism within the family, population growth is...

We estimated the economic benefits resulting from controlling soybean aphid infestation by using a multi-regional competitive dynamic equilibrium model. Results indicate that the reduction of soybean production resulting from a soybean aphid infestation is largely absorbed by reducing soybean...

Estimation of uncertainty using agronomic models typically requires a Monte Carlo study with a large number of simulations. Parallel computation dramatically speeds repetitive computation of this sort. The use of a Beowulf cluster parallel computer offers a low cost method of parallel computing...

Due to its modest data demands and transparent model structure, the Universal Soil Loss Equation (USLE) remains the most popular tool for water erosion hazard assessment. However, the model has several shortcomings, two of which are likely to have prominent implications for the model results....

In many regions of the U.S., low dissolved oxygen (DO) is a common freshwater impairment. States, territories, and tribes of the U.S. are required by federal law to develop Total Maximum Daily Loads (TMDLs) for waters not meeting established DO standards. Regulators and other professionals are...

Although the U.S. Congress established the Total Maximum Daily Load (TMDL) program in the original Clean Water Act of 1972, Section 303(d), it did not receive attention until the 1990s. Currently, two methods are available for tracking pollution in the environment and assessing the effectiveness...