search for: from_treelin

dear all i am trying to perform t-test (t.test) in R here i am putting the commands and answer i got > t.test(Ht_cm[from_treeline=='above'][type=='SD'],Ht_cm[from_treeline=='below'][type=='SD']) Welch Two Sample t-test data: Ht_cm[from_treeline == "above"][type == "SD"] and Ht_cm[from_treeline == "below"][type == "SD"] t = 1.4181, df = 159.203,...

Dear all I am trying to learn R I was trying to calculate standard deviation here are the commands and outputs in R > sd(Ht_cm[type=='SD'])[1] 3.283605> sd(Ht_cm[from_treeline=='above'])[1] 16.83289> sd(Ht_cm[type=='SD'][from_treeline=='above'])[1] NA> the problem is that, i could not understand why the third command could not give any result. please help me out thanking you Regard MS Nepal ______________________________...

Dear all I am learning R I am doing Z-test with package 'BSDA' here is my syntax and result: > sdgr.ztest<-z.test(growth[type=='SD'& from_treeline=='above'], + growth[type=='SD'& from_treeline=='below'],alternative = "two.sided", + mu = 0, sigma.x =(sd(growth[type=='SD'& from_treeline=='above'],na.rm = T)), + sigma.y =(sd(growth[type=='SD'& from_treeline=='below&...