Statalist,
What I have nonparametric data for 3 groups, 1 dependent variable (ratio)
and 2 independent variables (technique and analysis type). The questions I
want to test are: does the technique matter with respect to the ratio
result?, does the analysis type matter with respect to the ratio result? is
there a difference between the groups? If so what are these differences?
However, there is the possibility of interactions, so I should test for that
as well.
I think I want to use a Friedman test, but cannot seem to figure out how to
deal with interactions, and even more simplistically, I cannot seem to
replicate the results for the sample that is in the help file (pasted
below). Has any one had these problems too and is there a solution?
S t u d e n t
--------------------------------------------
T E S T 1 2 3 4 5 6 7 8
-----------------------------------------------------
1 90 60 45 48 58 72 25 85
2 62 81 92 76 70 75 95 72
3 60 91 85 81 90 76 93 80
If you enter this as three variables, then you can just type in
friedman varlist
and all is fine.
The results from the above data are:
Friedman = 2.8889
Kendall = 0.1376
p-value = 0.8951
Thanks for the help!
Ashley
A confused MSc student
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