AMMI Analysis

[HaroldCh14]

I make my AMMI analysis with metan but the results don´t coincide with agricolae and with the program in SAS. The PC are negative when should be positive and vice versa.

I don´t know what is happening, could be my mistake on the code?

Grettings, i hope your answer.

[TiagoOlivoto]

Dear @HaroldCh14,
I have observed such behavior sometimes. This seems to be related to the singular value decomposition method (https://stackoverflow.com/questions/31268493/different-result-from-sas-iml-and-r-in-svd-decomposition). However, the interpretation of results will not change. If you look at the biplot, the relationship between genotypes/environments will remain the same.

Since there is no clear bug, I will close this now. Please, feel free to email me if you need more information
Best regards

[HaroldCh14]

@TiagoOlivoto Thank you so much for your answer.

Best regards from Colombia.