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Abstract
The purpose of this study was to develop an improved procedure to estimate a previous diameter for ongrowth and nongrowth trees on plots sampled by variable radius plot sampling. However, the models built can be used whenever a previous diameter is required and the appropriate independent variables are available. Data for this study were from 1,965 remeasured forest inventory plots in the 1989 inventory of West Virginia conducted by the Northeastern Research Station’s Forest Inventory and Analysis (NEFIA) unit. The investigation focused on three areas. First, we investigated whether breaking the data into six groups based on the rank average diameter growth was superior to NEFIA’s procedure of breaking the data into seventeen species groups. Second, we investigated whether basal-area increment (BAI) was superior to diameter increment (DI) as a dependent variable. Finally, we investigated additional independent variables. Based on the R2, mean residual, mean absolute error, and root mean square error, the best model had six species groups, BAI as the dependent variable, and a slightly expanded set of independent variables.
Parent Publication
Citation
King, Susan L.; Arner, Stanford. 1999. Estimating previous diameter for ingrowth trees on remeasured horizontal point samples. In: Stringer, Jeffrey W.; Loftis, David L., eds. 1999. Proceedings, 12th central hardwood forest conference; 1999 February 28-March 1-2; Lexington, KY. Gen. Tech. Rep. SRS-24. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 293 p.
