generate data from a Laplace distr using MTB
use sample size of n=30
test the hypothesis H0:median=0 with the t test, T+ test and sign test
repeat these tests as the data median is shifted more and more to the right

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random 30 c1 ;
laplace 0 1 .
let c1 = c1 - median(c1)   # start with median exactly zero

onet c1 ;
test 0 .
Wtest  0  c1 ;
alternative 0 .
Stest  0  c1 ;
alternative 0 .

let c1 = c1 + .05        # raise the median of data by .05

# with copy-paste repeat the last 7 commands
# do it 5 to 10 times
# make a table of the results: median value (initial, initial+.05,etc)
# and the 3 p-values
# give an interpretation of the results