Forestry officials have recently opened up a new parcel of land to reafforestati
ID: 3304719 • Letter: F
Question
Forestry officials have recently opened up a new parcel of land to reafforestation but are concerned about the quality of the land to support good growth in Pinus Radiata. Seedlings were planted in both the exisiting reserve and the new parcel of land. Heights of seedlings (in centimetres) were measured after 8 months and growth compared. The results are given below Old Plot New Plot 166 156 160 169 167 170 169 155 158 163 156 143 151 172 156 160 156 136 157 157 150 161 156 173 (c) Perform a non-parametric test to analyze the same data.Explanation / Answer
lets perform the non parametric test of independent samples in R as shown below
old<- c(166,156,160,169,167,170,169,155,158,163)
new <-c(156,143,151,172,156,160,156,136,157,157,150,161,156,173)
wilcox.test(old,new)
The result is
> wilcox.test(old,new)
Wilcoxon rank sum test with continuity correction
data: old and new
W = 102.5, p-value = 0.05968
alternative hypothesis: true location shift is not equal to 0
as the p value is slighlty more than 0.05 , hence we fail to reject the null hypothesis
Ho : Heights of seedlings are not different across the old and the new plots
h1 : Heights of sedelings are statistically different across the old and the new plots