laenge <- rexp(20)
gew <- exp(log(laenge)+rnorm(20))
> laenge
 [1] 1.8120638 0.1630322 0.1688026 0.3337552 0.1973733 0.9728828 0.8988871
 [8] 0.2278483 0.5028021 2.5225487 0.1768373 0.9393400 5.0628683 0.4711056
[15] 0.4403639 1.3235383 2.1683043 0.1995263 0.6726950 0.2269434
> gew
 [1]  3.84960501  0.01355344  0.11381978  0.05619164  0.37272920  0.43197179
 [7]  0.92407025  0.88305147  1.26890202 10.16664873  0.37602822  1.25691655
[13] 22.60262179  0.14089083  0.59043674  0.48057862  0.65509040  0.52162463
[19]  0.32417516  0.51629644

plot(laenge,gew)
points(mean(laenge),mean(gew),col='red')


s <- sample(20,replace=TRUE)
points(mean(laenge[s]),mean(gew[s]),col='green')

for (i in 0:100) {
   s <- sample(20,replace=TRUE)
   points(mean(laenge[s]),mean(gew[s]),col='green')
}

b<-c()
a<-c()
for (i in 1:100) {
   s <- sample(20,replace=TRUE)
   a[i]<-mean(laenge[s])
   b[i]<-mean(gew[s])
}