Life sciences · the experiment
Keep the flock on budget
The authors' hypothesis: each pigeon can only spend a small entropy budget on leading or following. Set the flock's hierarchy to stay on budget, with two birds, then with eight.
1 · Keep two birds on budget
Beginner
According to the article, what happens to the hierarchy as the flock grows?
Two pigeons. Assume, as the authors do, that each bird has a fixed entropy budget. Set the hierarchy index η until the cost per bird equals that budget.
2 · Keep eight birds on budget
The bird of rank i influences the flock with probability e^−η(i−1): the leader, rank 1, counts 1.
Intermediate
In your flock of two, η ≈ 0.7. What influence probability does the bird of rank 2 have?
Eight pigeons, same budget per bird. Find the hierarchy that respects it.
3 · Double the flock
Your flock of eight is on budget. It grows to sixteen pigeons, with no change in hierarchy.
Expert
What happens to the cost per bird?
4 · Try perfect equality
With η = 0, everyone follows everyone: the wisdom of crowds.
Expert
What does this egalitarian flock cost, and what do the simulations show?
Budget kept
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