term is equal to N log((1 —δ)∕g)/ log λ. The first term converges to m1 by the argument
in the previous paragraph. Let us study m1. By the assumption that sj,t follows a
uniform distribution, we obtain Pr(s0 < 0) = μ. Then the number of producers who
adjust their capital at the first step, m1, follows a binomial distribution Bin(N,μ). By
the central limit theorem, m1∕-√zN — VNμ asymptotically follows a normal distribution
with mean zero and variance μ(1 — μ). Combining these results, we obtain that m0/y∕N
asymptotically follows a normal distribution with mean zero and variance μ(1 — μ).
Next we examine mu conditional to mu-1. We have Pr(j ∈ Hu|j ∈/
∪v=1,2,...,u-1Hv) = φ(log ku — log ku-1)/ log λ. Thus mu follows Bin(N —
∑u=1 mv, φ(log ku — log ku-1)/ log λ). This defines the stochastic process mu completely.
As we let ξ → 1 and N → ∞, the binomial converges to a Poisson distribution with
an asymptotic mean φmu-1 .
Since a Poisson distribution is infinitely divisible, the Poisson variable with mean
φmu-1 is equivalent to a mu-1 -times convolution of a Poisson variable with mean φ.
Thus the process mu is a branching process with a step random variable being a Poisson
with mean φ. Since φ ≤ 1, the process mu reaches 0 by a finite stopping time with
probability one. Thus the best response dynamics is a valid algorithm of equilibrium
selection. Let T denote the stopping time. Using the asymptotic formula, we have
W → ∑T=1 mu. By using the property of a Poisson branching process (Kingman
(1993)), we obtain the infinitely divisible distribution for the accumulated sum W =
∑t=1 mu as in the proposition.
References
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Bartelsman, E. J., and W. Gray (1996): “The NBER manufacturing productivity
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Caballero, R. J., and E. M. R. A. Engel (1991): “Dynamic (S,s) economies,”
Econometrica, 59, 1659-1686.
Caplin, A. S., and D. F. Spulber (1987): “Menu cost and the neutrality of money,”
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