Ex antevs.Ex post Ex ante moral hazard:behavior changes that occur before an insured event happens and make that event more likely. leaving the stove on skipping the flu vaccine Ex post moral hazard:behavior changes that occur after an insured event happens and make recovering from that event more expensive. using expensive drugs instead of generics knee replacement surgery instead of painkillers Bhattacharya,Hyde and Tu-HealthEconomics Bhattacharya, Hyde and Tu – Health Economics Ex ante vs. Ex post  Ex ante moral hazard: behavior changes that occur before an insured event happens and make that event more likely.  leaving the stove on  skipping the flu vaccine  Ex post moral hazard: behavior changes that occur after an insured event happens and make recovering from that event more expensive.  using expensive drugs instead of generics  knee replacement surgery instead of painkillers