Replaced with revised version of paper 07/27/06.

Confirming the precision agriculture hypothesis for variable rate nitrogen applications (VRA) has proven challenging. To confront this challenge, researchers have begun to use increasingly sophisticated statistical models to estimate and compare site-specific crop response functions. While...

Confirming the precision agriculture hypothesis for variable rate nitrogen applications (VRA) is challenging. To confront this challenge, researchers have used increasingly sophisticated statistical models to estimate and compare site-specific crop response functions (SSCRFs). While progress has...

We explore the value of soil test, topographical, and remote sensing information for guiding variable rate fertilizer applications in corn. Results suggest combining topographical and remote sensing information is more valuable than conventional soil tests. Considered separately, topographical...

This paper compares two estimation methods of a three-stage least squares (3SLS) system of equations, corrected for spatial autocorrelation. The modeling approach is novel in that it is an extension of Anselin's (1988) seemingly unrelated regression (SUR) space-time spatial error model for panel...

Site-specific application of manure has the potential to improve crop production and environmental quality. If manure is applied where it is needed, in the quantity required by the crop, over application, with attendant runoff and leaching problems can be reduced. To implement this approach...

Understanding the relationship between soil fertility dynamics and crop response is conceptually appealing. Even more appealing is comprehension of the spatial and temporal heterogeneity of these connections over a production surface and across seasons. Knowledge of these interactions is...