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The science
What the model is. Eight stakeholders each hold an opinion xi between 0 (oppose) and 1 (support) about a proposal. Every discussion round each person revises their view by averaging what the people they listen to think. Who listens to whom is a weighted directed graph; this is the DeGroot model of opinion dynamics, extended to the Friedkin-Johnsen model in which people stay partly anchored to their first opinion. It is a model of social influence on a network, not of management advice.
Trust matrix. Stakeholder i gives attention Aij ≥ 0 to j (set by the network type, the extra attention paid to the authority figure and the bridge weight between camps) and self-trust s. The row-stochastic trust matrix is
Wij = Aij / (s + Σk Aik), Wii = s / (s + Σk Aik), Σj Wij = 1
DeGroot / Friedkin-Johnsen update. With susceptibility ai (1 = fully open to others) and prejudice x0i (the starting opinion):
x(t+1) = Λ W x(t) + (I - Λ) x0, Λ = diag(a1, ..., a8)
If the matrix I - ΛW is invertible (every closed group of stakeholders contains someone with ai < 1) the opinions converge to the unique fixed point
x* = (I - ΛW)-1 (I - Λ) x0
and disagreement can persist forever: people who partly keep their first view never fully agree. If all ai = 1 and the graph is strongly connected with self-trust (so the chain is aperiodic), opinions converge to a consensus equal to the weighted mean
x∞ = π · x0, π W = π, Σ πi = 1
The stationary vector π is the long-run influence of each stakeholder: a person who is heavily listened to (the sponsor with a large authority weight, or the hub of the star network) gets a large πi and so drags the consensus toward their own view. The quantity π·x(t) is conserved by every round when a = 1, which the page checks. Because each new opinion is an average of old ones, no opinion ever leaves the range [min x0, max x0] (maximum principle).
Speed of agreement. The rate of convergence is set by the second-largest eigenvalue modulus of W. A thin bridge between two camps makes it close to 1, so agreement is very slow ("Two camps, thin bridge"); shortcuts in a ring or a dense forum make it much smaller. The page reports the number of rounds until every opinion is within 0.01 of the equilibrium.
Checks in the page. (1) the simulated all-susceptible limit against π·x0 with π from a linear solve; (2) the simulated fixed point against the direct matrix solution (I - ΛW)-1(I - Λ)x0 by Gaussian elimination; (3) the invariant π·x(t) after 60 rounds; (4) row sums of W; (5) the maximum principle. The 3D page also compares the drawn column heights with the model.
Honest simplifications. Eight abstract actors, one scalar opinion on one issue, fixed trust weights, no learning of who to trust, no noise, no bounded confidence, no strategic behaviour or bargaining. Real organisations are far messier; the model shows only how network structure, authority and anchoring shape agreement. Names are generic roles, not real people or companies.