It hasn't been removed, but you cannot see it in red triangle anymore (no idea why).
Names Default To Here(1);
dt = Open("$SAMPLE_DATA/Car Poll.jmp");
obj = dt << Partition(
Y(:country),
X(:sex, :marital status, :age, :type, :size),
Split Best(2)
);
obj << K Fold Crossvalidation(5);
Also you can see it in preferences:
![jthi_0-1634902007023.png jthi_0-1634902007023.png](https://community.jmp.com/t5/image/serverpage/image-id/36911i2B4FD6C055B55AE9/image-size/medium?v=v2&px=400)
But if you enable it, it will launch every time.
Also: Bring back the crossvalidation option in Partition platform menu
-Jarmo