I had that theory for a while. I figure if you're trying to avoid being mugged, you don't have to be invulnerable, just the second most vulnerable person a mugg

I had that theory for a while. I figure if you're trying to avoid being mugged, you don't have to be invulnerable, just the second most vulnerable person a mugger can see. If we had better data, we could even figure out if, e.g., a guy listening to an iPod is more vulnerable than a woman who isn't, or if it depends on age, or what.