So one thing traffic lights do is stop people dying. (Unless Freakonomics want to tell me otherwise) But they cost money and apps cost money, so how much are t

So one thing traffic lights do is stop people dying. (Unless Freakonomics want to tell me otherwise) But they cost money and apps cost money, so how much are the dead people worth? You then could just rely on the legalities I guess and ignore the article which was mostly about safety. Dead people cost a bit, but the elderly a lot less, sometimes you save money. Often we get these figures wrong because of emotions and it's hard to exactly quantify.