Options
correlation matrix
Sunnyboy_nh
Member Posts: 10 Newbie
how can I use the correlation matirx operator between attributes with different value types specifically between a nominal and a real/integer attribute?
Tagged:
0
Best Answer

OptionsTelcontar120 Moderator, RapidMiner Certified Analyst, RapidMiner Certified Expert, Member Posts: 1,635 UnicornAfter dummy coding, you will have a series of numerical (0/1) attributes for each nominal value. So for example if you started with a nominal attribute with 3 values (A,B,C), then you will end up with 3 new numerical attributes: value=A, value=B, and value=C. Each one will be a (0/1) numerical variable that tells you if that example had that value or not. These can be run in a correlation matrix with other numerical attributes. Check out the tutorial process for the Nominal to Numerical operator if you want to see this in action inside RapidMiner.
5
Answers
You should convert nominal to numerical first, generally using dummy coding, and then compute the correlation on the resulting data.
Lindon Ventures
Data Science Consulting from Certified RapidMiner Experts
Yes sure i also did a conversion to binominal first but doing that I get in the result matrix of correlation matrix instead of one converted attribute all of a sudden multiple of that same attribute each time wirh slightly different values which my matrix rows and column number which i don'need and i don't underestand .....!
What do exactly mean wirh dummy coding ?
Yes you are right. I don't want to do correlstion between two integer and real but to do correlation between integer or real # and polynominal ?
Lindon Ventures
Data Science Consulting from Certified RapidMiner Experts