Some good point, but also others that prove you never done and real self defence training.
Don't look like easy target- ie head up look confident, most attackers will look for easier target unless you shown them something shinny.
Distraction- gives you a few seconds to get out of range/danger.
If held stamp foot/rake heel down shin/elbow/reverse head butt/kick knee's/grab twist squeeze anything tender. Most of these should create time to get away or loosen holders grip enough for you to slip out.
If held round throat from behind turn your head 1st so you can breath, then use above.
If throat from front aim for same tender areas to get grip reduce plus throat/ flat hand slap over ear, eyes and nose last resort unless you want to end up on a murder charge (depends on your country's laws on amount of force allowed in self defence).
As to weapons use to throw again to distract ie keys wallet briefcase handbags etc.
Guns knifes your just a moron if you go up against those unless lots training, best to give them what they want and hope for best.( but tricky if your American with your wonderful gun laws)
Best not to look like easy pray or be there in 1st place.
Or go get some training on self defense ie breaking of locks and holds.
