Imputation and Model-Based Updating Techniques for Annual Forest Inventories

2001

S. 322-330

3 Abb., 3 Tab., 20 Lit. Ang.

Unselbständiges Werk

200088701

The USDA Forest Service is developing an annual inventory system to establish the capability of producing annual estimates of timber volume and related variables. The inventory system features measurement of an annual sample of field plots with options for updating data for plots measured in previous years. On imputation and two model-based updating techniques are described and evaluated with respect to the bias and precision of their annual estimates of basal area per unit area. The evaluation indicate that simple plot-level imputation and model-based updating techniques produce adequately unbiased and precise estimates of annual mean basal area per unit area for large areas.