what you see is a warning, because the Z-transformation can only be applied on numbers not on Strings.
From your screenshot I assume, that you used the Nominal to Numerical operator to change the address from String to numbersand probably the meta data haven't updated yet.
In general transforming strings to numbers (for example with dummy encoding) can be problematic, as you now allow more transformations and comparisons that might not make sense. For example you can compare Street_1 and Street_2 and say they are equal or not. If you transform them to 1 and 2then there is now a ranking as one value is bigger than the other.
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sgenzerAdministrator, Moderator, Employee, RapidMiner Certified Analyst, Community Manager, Member, University Professor, PM ModeratorPosts: 2,959 Community Manager
@David_A I would probably submit that this bubble message is not human-interpretable by many. Maybe we can clean this up, @Marco_Boeck ?
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