A bargaining solution balances fairness and efficiency if each player's payoff lies between the minimum and maximum of the payoffs assigned to him by the egalitarian and utilitarian solutions. In the 2-person bargaining problem, the Nash solution is the unique scale-invariant solution satisfying...

A bargaining solution guarantees minimal equity if each player's payoff is at least as large as the minimum of the payoffs assigned to him by the equal-gain (i.e., egalitarian) and equal-loss solutions. The Kalai-Smorodinsky solution is the unique scale-invariant 2-person solution with this...