[R] Duplicate row names are not allowed

[ville iiskola]

Hi
I read a book where was shown an example how to create a probability model with mlogit. I tried to do like the instruction said but i get error message that "duplicate row names are not allowed". What could i do to fix it?

I had the data in excel and imported it to R using R commander. I attach the data file and print sqreen of my code to here if somebody could help the novice. Ville
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