Before revision:  When this observation structure is sufficiently symmetric, the additional information aggregated by each generation is asymptotically equivalent to fewer than two independent signals , even when generations are arbitrarily large . When agents observe all predecessors from the previous generation, social learning aggregates no more than three signals per generation starting from the third generation, and the long-run learning rate is slower when generations are larger .
After revision:  When this observation structure is sufficiently symmetric, the additional information aggregated by each generation is asymptotically equivalent to fewer than two independent signals , even when generations are arbitrarily large .