期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
最大似然函数与回归结合法计算ED_(50) 被引量:1
1
作者 崔佳 高桂明 《数理医药学杂志》 1995年第4期313-314,共2页
通过利用指数回归模型的结果,本文描述一种简便的最大似然函数法估计计算ED_(50),并通过求这两种方法所得ED_(50)估计值的平均值,提高估计值的精确度。
关键词 医用数学 ED50 最大似然函数 回归结合法
下载PDF
Small-area estimation of forest stand structure in Jalisco, Mexico 被引量:1
2
作者 Robin M. Reich Celedonio Aguirre-Bravo 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第4期285-292,I0004,共9页
Natural resource statistics are often unavailable for small ecological or economic regions and policymakers have to rely on state-level datasets to evaluate the status of their resources (i.e., forests, rangelands, g... Natural resource statistics are often unavailable for small ecological or economic regions and policymakers have to rely on state-level datasets to evaluate the status of their resources (i.e., forests, rangelands, grasslands, agriculture, etc.) at the regional or local level. These resources can be evaluated using small-area estimation techniques. However, it is unknown which small area technique produces the most valid and precise results. The reliability and accuracy of two methods, synthetic and regression estimators, used in smallarea analyses, were examined in this study. The two small-area analysis methods were applied to data from Jalisco's state-wide natural resource inventory to examine how well each technique predicted selected characteristics of forest stand structure. The regression method produced the most valid and precise estimates of forest stand characteristics at multiple geographical scales. Therefore, state and local resource managers should utilize the regression method unless appropriate auxiliary information is not available. 展开更多
关键词 forest structure regression estimator synthetic estimator spatial model stratified random sampling satellite imagery inventory and monitoring
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部