> Crash rates can be adjusted to account for differences in environment and demographics in different data sets. A sample dataset with acrash rateris exposed to

> Crash rates can be adjusted to account for differences in environment and demographics in different data sets. A sample dataset with acrash rateris exposed to some variableiat a different proportion p than the comparison dataset. In the case study, for example, vehicles running Autopilot were driven on freeways (i) 93% of the time, resulting in pi= 0.93. In the SHRP 2 NDS, only 28% ofvehicle mileage was recorded on freeways, i.e pi= 0.28. In the SHRP 2 NDS data, vehicles on non-freeways crashed 2.01 times more often per mile than vehicles on freeways. The observed Autopilot crash rate can be adjusted to reflect national driving ratesto reflect the crash rate that might be observed if 28% of Autopilot mileage was on freeways and 72% were on non-freeways, assuming that the 2.01 ratio holds for Autopilot. So if humans are 2 times more likely to crash on non-highways than highways, the argument presented here is that the added danger of non-freeways affects autopilot in the same way, degrading its performance. Seems like a far reaching assumption. If there is no data on autopilot performance on rural roads, then you cannot make a claim either way.