ARS | Publication request: Comparing Correlated Parameter Estimates for Nonlinear Pet Model

Submitted to: Meeting Abstract
Publication Type: Proceedings/Symposium
Publication Acceptance Date: April 1, 2003
Publication Date: April 27, 2003
Citation: WU, J., PARKHURST, A., ESKRIDGE, K., TRAVNICEK, D., BROWN BRANDL, T.M., EIGENBERG, R.A., HAHN, G.L., NIENABER, J.A., MADER, T., SPIERS, D. COMPARING CORRELATED PARAMETER ESTIMATES FOR NONLINEAR PET MODEL. MEETING ABSTRACT. 2003.

Technical Abstract: The nonlinear PET model based on Newton's law of cooling can be used to estimate body temperature in cattle, Tb, challenged by hot cyclic chamber temperatures, Ta. The PET model has four biologically meaningful parameters: kappa, the thermal constant, delta, the difference between Tb and adjusted Ta; gamma, the proportion of variance in Tb comparable to variance in Ta; Tb initial, the body temperature at time zero. The two parameters gamma and delta are highly correlated in the current version of the model. This study looks at other ways to parameterize the PET model in an effort to reduce the correlation between parameters and improve nonlinear behaviors, such as parameter-effect curvature, bias, excess variance, and skewness.