Preprint #01-21 SMALL AREA ESTIMATION IN A WATERSHED EROSION ASSESSMENT SURVEY by
نویسندگان
چکیده
This article describes an application of small area estimation in a survey conducted in the Rathbun Lake Watershed in Iowa (USA). The estimator considered is an extension of the mixed effects regression model of Battese, Harter and Fuller (1988). From a sample of 183 plots in the watershed, erosion from four sources as well as total erosion are estimated for 61 small areas within the study region. Information on land cover and topography from GIS coverages are used to create plot-level covariates for the regression model. Two estimators are discussed in the article: an empirical best linear unbiased predictor, and a composite estimator. The latter estimator is potentially less efficient than the former, but preserves the additivity between the estimates for the four erosion sources and the total erosion. For this survey, the estimated efficiency loss is shown to be very small.
منابع مشابه
Small Area Estimation in a Watershed Erosion Assessment Survey
This article describes an applicationof small area estimation in a survey conducted in the Rathbun Lake Watershed in Iowa (USA). From a sample of 183 plots in the watershed, erosion from four sources as well as total erosion are estimated for 61 small areas within the study region. Information on land cover and topography from GIS coverages are used to create plot-level covariates for the regre...
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This article describes the sampling design, survey methodology and findings of a natural resources survey conducted in the Rathbun Lake Watershed in Southern Iowa in 1999-2000. The goal of the survey was to quantify the erosion from all sources on agricultural lands and the ecological health of streams for each of 61 subwatersheds in the area. A total of 183 plots of approximately 160 acres in ...
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