I have heard that German Shepherds can be very protective of their family and that can lead to unwarranted attacks on others who the dog views as a threat to his family. Not sure why Boxers have high enough statistics to be on the list, but they do.

A point that I would find interesting is the demographic breakdown of owners of dogs that have maliciously attacked or killed someone (or other animal). Taking care of dogs is not cheap, and some breeds of dogs are definitely more high maintenance than others. An owner from a lower income bracket may not have the resources to manage their dog as is needed. In other words, if the majority of dog attacks are committed by dogs owned by those without sufficient means to care for them, that could be a greater causality for dog attacks than just judging by breed alone.