Evaluating and Improving Models

Separate choosing from checking

The inner scores tie

Botie is tempted to choose a setting from the outer scores. Keep the selection inside its allowed data boundary.

BOTIE

The first inner row ties, while the second outer candidate looks better. Which choice respects the protocol?
The inputs we are comparing

Inner losses by fold and candidate

The outer scores tempt a different choice

12
31

Tied inner results

22
13

Outer losses by fold and candidate

The outer scores tempt a different choice

42
25

Tied inner results

71
32
Result for the outer scores tempt a different choice
4.5
Choose an explanation to test
The candidate order changes

This check uses the pieces from “Give the search an outside assessment”.

BOTIE

The lowest inner losses now occur in columns 2 and 0 (zero-based). Predict the selected outer scores and their mean.
Inner losses by fold and candidate
541
132
Outer losses by fold and candidate
128
610

Use a number, text, or an array matching the requested result. For a matrix, put each row in brackets. Saving your prediction runs your current construction on these inputs and checks the earlier examples too.

Build a construction in the workspace above first. This case will test those pieces.

If outer errors cause you to add another feature, what role have those observations now played?

Assessment data that guides a revision has become development evidence.

Recorded losses audit the protocol. A real nested run must also enforce split boundaries while fitting each complete pipeline.

Work through the Python challenges →
Continue the courseIs the Model Wrong, or Is the Record Wrong? →
← Did the Revision Help on the Same Cases?