earticle

영어

This study is about statistical analysis for growth in species of major trees using in thinning out trees data. Pine forests (Northern Forest Service) used the growth data for three years from 2012 to 2015. And nut pine forests (Eastern Forest Service, Southern Forest Service) used the growth data for three years from 2014 to 2017. And larch forests used the growth data for three years from 2013 to 2016. Lastly, oak tree forests used the growth data for three years from 2014 to 2017. We take growth of the diameter of each species for response variable, and degree of thinning and level of trees, local(cites and counties), age-class(of trees) for the covariates. We focus on comparing the difference of the diameter growth according to each covariates. We use ANOVA for analysis of the difference in the amount of growth in diameter, Tukey's multiple comparisons for post analysis, and regression trees for analysis of a major effect on the growth of diameter. We get some results that the effects of the thinning increase the growth of diameter although there is a degree of difference depending on the region, and there is a difference in the growth of trees according to the level of trees.