非诚勿扰 王磊
摘要 以2块热带季雨林白颜树优势树种为研究对象，采用多元逐步回归方法，研究其组成树种的单株木冠幅面积年均变化量预测模型，因变量为单株木冠幅面积，自变量包括胸径、树高、枝下高、低叶高，共测定了24株树木，全部参加了建模，最终建立了白颜树的冠幅面积预测模型。结果表明，枝下高、低叶高和胸径是影响白颜树冠幅面积的重要因子；模型的调整决定系数为0.467；标准误差较小，为0.204李玉刚 水墨丹青，说明模型的可靠性大；模型的回归关系系数为0.005，回归关系统计意义明显；冠幅面积与胸径、枝下高、低叶高的P值检验分别为0.045、0.004、0.002，说明其回归关系显著，本文对冠幅面积变化量进行的回归预测模型是有意义的且具有一定的实用性。
关键词 白颜树；冠幅面积；逐步回归模型
中图分类号 S718.5 文献标识码潮湿的心歌词 A 文章编号 1007-5739（2018）14-0152-03
Abstract Based on two dominant tree species in tropical monsoon rainforest，the prediction model of average annual variation of crown area was studied by using multivariate stepwise regression method.The dependent variable was the crown width area of individual tree，independent variable included diameter at breast height，height of tree，height under branch，height of low leaf.A total of 24 trees were tested and participated in modeling.Finally，the prediction model of the crown area was established.The results showed that，the height of branches，the height of lower leaves and the diameter of breast height were the important factors affecting the crown area of Gironniera subaequalis，钢琴考级二月里来the adjustment decision coefficient of the model was 0.467，the standard error was 0.204，which indicated that the reliability of the model was high.The regression coefficient of the model was 0.005，the statistical significance of the regression relationship was obvious刘亦菲简介，and the P value test of the crown area and diameter of breast height，the height under branch and the height of lower leaf was 0.045，0.004 and 0.002，respectively，which indicated that the regression relationship was significant.To sum up，周星驰女儿the regression prediction model for the variation of crown area is meaningful and practical.
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