That entities are choosing to accept negative rates is certainly true (at least until paper currency is phased out, then it perhaps would be more debatable), but as far as I can tell, this is a nonsequitur. European banks are offering negative rates to savers because they are mandated to maintain reserves with the ECB, and the ECB is offering negative rates on reserves. The rate on reserves in turn drives the rate of inter-bank lending. So, it seems reasonable to me to ask what the market rate would be were the central bank not offering any interest on reserves, nor trying to set the rate of inter-bank lending, nor any similar rate. Would the market rate be negative, or zero, or slightly positive, or substantially positive? Have any economists taken a stab at the question? If not, why not?