ilm=read.table("http://www.tlu.ee/~jaagup/andmed/ilm/harkutund.txt", sep=",", header=TRUE)
jaankesk=ilm[ilm$Kuu==1,]$TA1H
mean(jaankesk)
sd(jaankesk)
#Samast üldkogumist võetud juhuslike valmite aritmeetiliste keskmiste jaotuse standardhälve on
#ligikaudu võrdne valimi standardhälve jagatuna ruutjuurega valimi suurusest
yldkogumi_keskmise_toenaosus=sd(jaankesk)/sqrt(length(jaankesk))

Warning message:
In normalizePath(path.expand(path), winslash, mustWork) :
  path[1]="\\edu.lan\users\real\Personal\jaagup0299\My Documents/R/win-library/3.2": Juurdepääs on keelatud

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[Previously saved workspace restored]

> yldpikkused=rnorm(30000, 170, 10)
> head(yldpikkused)
[1] 178.8666 171.3051 158.4803 156.4802 178.0614 168.9423
> sample(yldpikkused, 5)
[1] 169.8146 171.4180 160.2149 146.4697 164.9695
> sample(yldpikkused, 5)
[1] 176.4412 154.6126 180.8899 168.7376 167.0042
> mean(sample(yldpikkused, 5))
[1] 166.0853
> mean(sample(yldpikkused, 5))
[1] 169.562
> mean(sample(yldpikkused, 5))
[1] 171.8247
> mean(sample(yldpikkused, 5))
[1] 172.2317
> mean(sample(yldpikkused, 5))
[1] 167.7247
> valim=sample(yldpikkused, 5)
> valim
[1] 180.6650 163.4499 167.1458 178.6620 156.7967
> mean(valim)
[1] 169.3439
> sd(valim)
[1] 10.14887
> delta=sd(valim)/sqrt(length(valim))
> delta
[1] 4.538714
> sd(valim)+delta
[1] 14.68759
> mean(valim)+delta
[1] 173.8826
> mean(valim)-delta
[1] 164.8052
>