Roles and Labels - A Quick Guide

sgenzersgenzer 12Administrator, Moderator, Employee, RapidMiner Certified Analyst, Community Manager, Member, University Professor, PM Moderator Posts: 2,279  Community Manager
edited December 2018 in Knowledge Base
I continue to see many users get puzzled by "roles" and "labels" in RapidMiner Studio. Here's the simplest way I can explain it...

The ID role


Your typical data set has rows and columns (known as "examples" and "attributes" in RapidMiner Studio. Columns are also sometimes known as "features".). You can do most things with these attributes just the way they are:



But sometimes you want to give some attributes special "roles" for various reasons. For example, the most common role is an "id":



You see here that there is a NEW, BLUE attribute on the left that I called "sonarID". I made it an 'id' attribute because its ID numbers are unique and should NOT be used in modeling or other purposes. This id column is also useful if you want to join it with other data sets.

How did I make this make this column an 'id'? I used the SET ROLE operator:



The Set Role operator is very easy to use. You select the attribute whose role you want to change (usually from "regular" = no role at all) to some other role. I set it to 'id' in this case. Easy!

The Label Role

The 'label' role is one of the most important roles in RapidMiner. It indicates which attribute is the predicted class when used in any modeling operator:



This ExampleSet has a new attribute called "Prediction" but you will get a error if you try to use it as it does not have the 'label' role:



Now I use the Set Role operator to change this attribute to 'label':



And voilà! My ExampleSet is ready for modeling.



Other Roles


So what are the other roles and what are they used for? Let's just create a master list....

regular (white) = no role at all - just a plain attribute

id (blue) = an attribute that contains values (numerical or nominal/polynominal) that are unique to this example - i.e. an ID number.

label (green) = an attribute that contains values (numerical or nominal/polynominal) that will be the predicted class for a modeling operator later on. - i.e. the dependent variable or the column of values you want to predict

prediction (green) = an attribute that contains the predicted values (numerical or nominal/polynominal) after a model is applied on new, unseen data.

confidence (yellow) = an attribute that contains numerical confidence values pertaining to a prediction.

cluster (yellow) = an attribute that contains nominal/polynominal values that map an example to a particular cluster - e.g. the result of using a clustering operator like k-means

weight (pink) = an attribute that contains the 'weights' of examples with regard to the label. Weights are used in learning processes to set the importance of examples.

Special Attributes


Don't forget that if an attribute has a role, it is now considered a 'special attribute' and hence must be manually included in many operators such as Select Attributes or Filter Examples:


.
That's about it! Enjoy and happy RapidMining!

Scott

sgenzerTelcontar120lionelderkrikorvarunm1eackley29yyhuang

Comments

  • reemhreemh Member Posts: 1 Newbie
    Thanks so much! This was such a helpful article. I just dipped my toes in RapidMiner so it's no surprise I'm struggling. Thanks again. 
    mschmitzsgenzer
  • TerpdogTerpdog Member Posts: 1 Newbie
    How did you get the dialog where you could select the attribute and assign a role. I have been trying to do this for 3 hours and I can get nothing but a dialog to select the attribute and it has nothing about the role. I am about to uninstall Rapidminer.

  • sgenzersgenzer 12Administrator, Moderator, Employee, RapidMiner Certified Analyst, Community Manager, Member, University Professor, PM Moderator Posts: 2,279  Community Manager
    hi @Terpdog you need to use the "Set Role" operator. Then you can change the role in the Parameters panel.

    Scott

  • IngoRMIngoRM Administrator, Moderator, Employee, RapidMiner Certified Analyst, RapidMiner Certified Expert, Community Manager, RMResearcher, Member, University Professor Posts: 1,596  RM Founder
    You also may want to check out RapidMiner Academy, there are videos on this topic, for example:
    sgenzer
Sign In or Register to comment.