Artificial Intelligence / Unit 2 AI 0107 worked example, 60 to 90 seconds
A-star Beats the Gorge
The idea
Replaying the gorge under spent-plus-estimated scoring shows a lure inspected, priced, and declined.
In practice
Same map, same honest estimates. Camp scores 0 plus 3. Extending: Camp–Cliff scores 1 plus 1 — 2; Camp–Bridge scores 3 plus 2 — 5. A-star, like greedy, is seduced: it extends the Cliff path first. But the extension Camp–Cliff–Lodge now scores 11 plus 0 — eleven — and the meter has told the truth. The frontier's best is Camp–Bridge at 5, which extends to Camp–Bridge–Lodge at 6, which is selected, goal-tested, and returned. Four selections, optimal answer, and the switchback was examined exactly long enough to be rejected — the meter, not any map-reader's instinct, did the rejecting.
Where people slip
The lure was not avoided — it was inspected and out-priced. Optimism costs time; it does not cost the answer.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Unlocks
- Nothing yet depends on this.
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