|Ban mobile phone use while driving||Don't ban mobile phone use while driving|
|Mobile phone use while driving causes more deaths than it saves ||0||Type I Error |
|Mobile phone use while driving saves more deaths than it causes||Type II Error |
Type I Error Costs If distracted drivers only killed themselves, why stop them? The hidden cost is that they typically run into someone else or they take their passengers with them. Drivers may be less careful with other peoples' lives. So, the Type I error costs are all the innocents killed by distracted drivers. This has been the focus of most of the studies and the policy.
Type II Error Costs Drivers with mobile phones have related information during Amber alerts. They have notified media outlets when traffic was bad due to wrecks and thus saved thousands of hours in commute time - during which some wreck could have occurred. They have been able to coordinate with their called parties, getting directions, etc., which saves time which has some value. And of course, they derive utility from the call. But if your job is highway safety, as board member of NTSB, how much do you value these? Since no one writes news stories about the wreck that did not occur from accurate traffic updates, they are largely hidden. Also, if your job is highway safety, you may not value lost time and utility as much as those who must give it up.
Let me repeat that I suspect that banning mobile phone use while driving is likely appropriate. I am just not certain that all the costs went into the decision.