> Why is 0 terrible if it's also on the efficiency frontier? When would this be the case? I'm having trouble picturing it. > And what's you moral argument fo

> Why is 0 terrible if it's also on the efficiency frontier? When would this be the case? I'm having trouble picturing it. > And what's you moral argument for the level of fraud at the frontier? The frontier is exactly the point at which you cannot reduce the amount of fraud without it costing genuine users (and you) more than you gain. So if you're at the frontier and you want to reduce the amount of fraud further, you are acknowledging that harms to users are less important to you than losses from fraud, and doing so would be immoral. The efficient frontier should be the point of least moral harm, almost by definition - at least, as long as all the relevant externalities are priced in. > Is the same efficiency better with lower levels of fraud or higher or indeterminate? That's a trolley problem question. Higher levels of fraud at the same level of efficiency would mean there's a corresponding rise in value delivered from genuine usage of the service, so cost/benefit is the same and preference boils down to personal choice. But it sidesteps the more difficult question, which is how taking action to reduce the level of fraud actually plays out: there'll be diminishing returns as you take more and more extreme steps. Each step will likely have an incrementally more harmful effect on the genuine users, so efficiency won't remain the same.