Title: Sensitivity of FIA Volume Estimates to Changes in Stratum Weights and Number of Strata

Author: Westfall, James A.; Hoppus, Michael

Year: 2005

Publication: In: McRoberts, Ronald E.; Reams, Gregory A.; Van Deusen, Paul C.; McWilliams, William H.; Cieszewski, Chris J., eds. Proceedings of the fourth annual forest inventory and analysis symposium; Gen. Tech. Rep. NC-252. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central Research Station. 193-197

Abstract: In the Northeast region, the USDA Forest Service Forest Inventory and Analysis (FIA) program utilizes stratified sampling techniques to improve the precision of population estimates. Recently, interpretation of aerial photographs was replaced with classified remotely sensed imagery to determine stratum weights and plot stratum assignments. However, stratum weights based on remotely sensed data depend on many factors, such as classification algorithm and image selection. County volume estimates and associated variances were calculated over a range of stratum weight scenarios and for various number of strata. Rates of change in estimated values and variances, and their effects on percent sampling error, were examined in relation to different strata configurations.