מחיר תעופה

PNAS 2001, 98:1089-1094

What should I maximize?1. Gain/time2. Net gain/time3. gain/cost (Efficiency)

FlightGain/time (Gain-cost)/time Gain/cost

(Gain)

מחיר תעופה

מחיר הליכה

PNAS 2001, 98:1089-1094

cf=cw

What should I maximize?1. Gain/time2. Net gain/time3. gain/cost (Efficiency)

Flight = Walking Gain/time = Gain/time (Gain-cost)/time = (Gain-cost)/time Gain/cost = Gain/cost

(Gain)