Signaling, network externalities, and subsidies

A signal may be more effective the greater the number of people who use the same signal, thereby creating a network externality and potentially generating multiple equilibria. A subsidy to the signal can increase efficiency, and the signalers may benefit from the subsidy even if they pay taxes to finance it. But people who benefit from the signal may oppose too large a subsidy, because a large subsidy could destroy the signaling value.