Data Preparation
Move the zero point
BOTIE
Examples, experiments and workspace controls
Connect a tool's inputs to see what it produces. You can try a branch before connecting it to Result.
Try your own inputs
Use a copy of the example to try your own data. Keep the problem's assumptions in mind, and predict the effect of a change before checking the output. You can also add another branch to compare two ways of doing the calculation.
Context for this challenge
Find the training mean, then express each incoming reading relative to that mean. Keep the new reading out of the calculation of the reference point.
The training group's heights establish a reference for a new person. Botie must describe the newcomer without letting that person move the reference.
Calculate the training mean from its total and count, then subtract that mean from the new height.
Examples and results
- Training heights (cm)
- 0160
- 1170
- 2180
- New height (cm)
172
- Required result
2
Try a fresh construction
This clears this draft, including its undo history. Earlier successful attempts stay recorded. Build again without opening hints to record an independent attempt.
Stuck? Inspect a worked construction
The tools below form one possible solution. You can assemble it, follow its signals, and undo that change to return to your own construction.
Assumptions and test precision
This is a small construction problem. The lesson explains the assumptions and the parts of the full method that this example leaves out. Numerical tests allow a difference of 0.001. Lists and structures must also have the right shape.
Repeated heights affect the reference
This check uses the pieces from “Express a new height relative to the training group”.
BOTIE
- Training heights (cm)
- 0150
- 1150
- 2180
- New height (cm)
155
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.
Trace the new-height wire. How does its route show that the new person cannot change the fitted centre?
A transformed observation should use the reference learned during training, even if it lies far outside that group.
This is a small construction problem. The lesson explains the assumptions and the parts of the full method that this example leaves out.
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