Estimating the Uncertainty In Diameter Growth Model Predictions and Its Effects On The Uncertainty of Annual Inventory Estimates

Abstract

Uncertainty in diameter growth predictions is attributed to three general sources: measurement error or sampling variability in predictor variables, parameter covariances, and residual or unexplained variation around model expectations. Using measurement error and sampling variability distributions obtained from the literature and Monte Carlo simulation methods, the uncertainty in 10-year diameter growth model predictions is estimated as are its effects on annual basal area estimates obtained using an annual inventory system. The results indicate that although annual diameter growth is difficult to predict precisely, the effects of the uncertainty in the growth predictions are greatly attenuated when diameter estimates are aggregated to estimate plot basal area and mean basal area over all plots.

Citation

McRoberts, Ronald E.; Lessard, Veronica C. 2001. Estimating the Uncertainty In Diameter Growth Model Predictions and Its Effects On The Uncertainty of Annual Inventory Estimates. In: Reams, Gregory A.; McRoberts, Ronald E.; Van Deusen, Paul C., eds. 2001. Proceedings of the second annual Forest Inventory and Analysis symposium; 2000 October 17-18; Salt Lake City, UT. Gen. Tech. Rep. SRS-47. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. pp. 70-75