F28 · Topic 5.4
Crowdsourced accessibility map
1. Predict first
Eight reports come from the centre and 2 from the outskirts. A second report repeats the same original source. Does it independently confirm the observation?
Change it · step through · explain
Change an input, predict what will happen, then advance one step. Read why the state changes, reset and experiment. This fixed teaching model does not save progress or award XP.
Ready · Make a prediction
- Input 18Waiting
- Input 22Waiting
- Input 3same-sourceWaiting
Ready to experiment
Why: Predict the first change, then advance one step.
Try this: Keep the counts fixed and change provenance. Then set both counts to zero.
2. Build your procedure
Write a reporting workflow with unconfirmed, corroborated-under-the-rule and needs-update states. Require current independent evidence and moderator review, then propose recruitment to address coverage gaps.
Use AP CSP pseudocode, a language you know, or precise plain language. Your code is not executed here. Use the classroom assignment to save your response.
3. Check boundaries
| Input | Expected | Why this case |
|---|---|---|
| 8 centre,2 outer; same-source | 80%/20%; unconfirmed | Copied reports are not independent. |
| 8 centre,2 outer; corroborated | Meets the stated corroboration rule, not guaranteed true | A rule reduces uncertainty without eliminating it. |
| 8 centre,2 outer; stale | Needs update | Past evidence may no longer describe current conditions. |
4. Explain and reflect
Why could requiring more evidence both improve quality and harm some users?
Model limits: Fictional aggregate reports and evidence labels, not a real map or an automated truth detector. Do not enter real addresses or reports.