Skip to main content
The Evaluation component takes true target values and model predictions and computes performance metrics and visualizations. Its Actual port accepts as many wires as you like, so one node grades the whole grid: every model Inference scored, against every partition whose true labels reach it.

The grid

Wire Data Splitting’s Train y, Val y and Test y all into the Actual port. Each one is matched to the partition Inference used by reading the handle it came from, so nothing has to be configured. The report then reads:
  • Models down one axis — which algorithm is actually better.
  • Data sets across the other — whether that is true on data the model has never seen.

The gap

The scoreboard adds a Gap column: the training score minus the most held-out score. It is the single number that says whether a result is real. For error metrics (MAE, MSE, RMSE, MAPE) the sign is flipped before it is read, since a lower training error is the overfit direction.

Configuration

Which sets to grade is chosen on the node card rather than here, for the same reason Inference’s rosters are: it is a fact about the wiring, and the options only exist once the wires do.

Classification metrics

Regression metrics

The report

Everything in the report is additive. A control bar across the top carries one chip per data set and one per model; ticking Validation adds a column, a series and a matrix — it never takes Test away. Every panel below renders the cross product of what is ticked, so “how does the forest do on validation versus test, next to the regression” is answered by looking rather than by clicking back and forth. Colour carries one meaning throughout, the same rule the canvas runs on: hue is the data set. Models are told apart by position, label and line dash. The scoreboard’s row and column headers are themselves the selection controls, so narrowing the comparison happens where the comparison is. The last remaining chip in each row cannot be un-ticked; an empty report is never what un-ticking the last one means.

Headline numbers

The node card, the Overview page and the model version history each have room for one number. That number is the best-scoring model on the most held-out partition available — test where there is one, then validation, then the full frame, and only training as a last resort. A card reporting training accuracy would be a lie by omission.

Input / Output

Notes

  • A partition wired into Inference but not into Evaluation is called out in the report rather than silently dropped.
  • Actual and Predicted are matched by row index, so a partition arriving in a different order than it was scored in still lines up.