I believe that American crime literature indicates that the presence of guns offers general protective effects against home robberies for the entire region, and

I believe that American crime literature indicates that the presence of guns offers general protective effects against home robberies for the entire region, and that the visible presence of alarms offers very specific protective effects for that home alone (while pushing the crime to other homes), and that the presence of invisible alarms confers a modicum of protection to the region. I'm inclined to believe that this will push home robberies onto those without guns.