Before revision:  We say that there is strong learning when beliefs converge to the truth and there is weak learning when equilibrium flows converge to those under complete information. Our main result is a characterization of the  networks for which learning occurs for all increasing cost functions, given highly variable demand .
After revision:  We say that there is strong learning when beliefs converge to the truth and there is weak learning when the equilibrium flow converges to the networks for which learning occurs for all increasing cost functions, given highly variable demand .