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Classical Machine Learning

Ask a few neighbours

BOTIE

Measure query-to-reference distances, rank them, keep the first three indices and gather those labels.
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0 passed · 0 failed · 1 not run

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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.

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Context for this challenge

Measure query-to-reference distances, rank them, keep the first three indices and gather those labels.

We have an unfamiliar specimen and measurements of specimens whose classes are known. Instead of fitting a new decision formula, let's find nearby references and ask their labels for a vote. The measurements have already been put on a common scale.

Inspect the component calculation
Gather selected entries(
  Data table: Known specimen classes
  Indices: Take a range(
    List: Rank from smallest(
      Scores: Squared distances(
        Query vector: Unknown specimen measurements
        Candidate rows: Reference specimen measurements
      )
    )
    First index: 0
    Stop before: 3
  )
)
Examples and results
Known specimen classes
  1. 00
  2. 11
  3. 21
  4. 30
  5. 40
Unknown specimen measurements
  1. 00
  2. 10
Reference specimen measurements
0.10
0.20
0.30
20
30
Required result
  1. 00
  2. 11
  3. 21
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.

Your last tested pieces can start the full construction. An existing draft there keeps its own pieces.

An exact match loses the local vote

This check uses the pieces from “Turn three neighbour labels into a vote”.

BOTIE

One reference matches the query exactly, but the next two nearest references have the other class. Predict the existing three-neighbour majority rule's decision.
Unknown specimen measurements
  1. 01
  2. 11
Reference specimen measurements
11
1.11
11.2
55
88
Known specimen classes
  1. 00
  2. 11
  3. 21
  4. 30
  5. 40

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.

Which wire would reveal a bug that ranks distances correctly but gathers the wrong labels?

Neighbour methods require a meaningful distance and a reliable mapping from selected rows to their stored answers.

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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