A computer receives data detailing operation of a plurality of at least partially manually operated automobiles. The computer determines one or more trends in the operation of the plurality of at least partially manually operated automobiles, based at least in part on the data detailing the operation of the plurality of manually operated vehicles. The computer generates one or more operational rules, based, at least in part, on the one or more trends. The computer transmits the one or more operational rules to one or more at least semi-autonomous vehicles.