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Neural Networks

Repair a noisy memory

BOTIE

Repair the first bit from the other bits' weighted vote. The diagonal weight is zero, so the corrupted bit should not vote for itself.
Ready to test
0 passed · 0 failed · 1 not run

An empty floor. Start with the information your machine needs.

Received result

Your answer will arrive here.

Examples, experiments and workspace controls
Live values

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.

Start at an output arrow, then click or drag to an input. Drag empty space to pan. Delete removes a selection. Ctrl/Cmd+Z undoes a change.
Context for this challenge

Repair the first bit from the other bits' weighted vote. The diagonal weight is zero, so the corrupted bit should not vote for itself.

One bit of Botie's stored pattern is corrupted. Other bits can vote for a repair, while the damaged bit's self-connection must contribute nothing.

Combine the memory state with the supplied incoming weights and use the sign of that weighted vote.

Examples and results
Current memory state
  1. 0-1
  2. 11
  3. 2-1
First bit's incoming weights
  1. 00
  2. 11
  3. 2-1
Required result
1
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.

The first memory bit receives tied evidence

This check uses the pieces from “Repair the first bit from its neighbours' votes”.

BOTIE

Update only the first memory bit from its incoming weighted state. Use this workshop's binary convention: a nonnegative score produces 1, including an exact zero.
Current memory state
  1. 01
  2. 11
  3. 21
First bit's incoming weights
  1. 00
  2. 11
  3. 2-1

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.

Why would allowing a strong self-connection make a damaged bit harder to repair?

One local memory update does not establish that every corrupted pattern will converge to its intended memory.

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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