In linear regression, which Rapid Miner operator is used to connect training data set stream with scoring data set stream?

• A. Apply Model
• B. Train Model
• C. Apply Predictor
• D. Score Data

Answer: (A)

When you want to use what you learned from training data on new, scoring data in RapidMiner, you apply the trained model to the scoring dataset. The operator that does this bridging is Apply Model: it takes the model produced by the training step and the scoring data as input and outputs predictions for each row. This is why it’s the best choice—Train Model creates the model, but doesn’t run it on new data; Score Data computes metrics from predictions (and true values) but needs those predictions first; Apply Predictor can apply a pre-built predictor in some contexts, but the standard way to connect training and scoring streams is through Apply Model.