Gini for metric output

[danieleewww]

Is possible to put Gini into evaluation function?

[kaz-Anova]

I can add it , yes. However for a binary problem, you can use AUC. Gini=(2 * AUC) -1.

so if AUC is 0.640, Gini is 0.28 ( 2 * 0.64= 1.28 )-1). Higher AUC is higher GINI and vice verca - always. The relationship is monotonic.