I'm fairly new to the dog board as I normlly frequent a specific animal forum with a dog section.
I've noticed on MN that larger dogs seem to have a reputation as "child eaters". I personally don't agree with this but can see where this would stem from and how if a larger dog bites it causes more damage than a smaller dog.
I also believe that the reason smaller breeds are seen as less aggressive is because when they attack it is does not generally require medical attention and simply does not get reported so smaller dog attack statistics are lower.
This is not supposed to start a debate or a bunfight but is just a study I found interesting and thought that dog lovers may find it as interesting as I did.
This link provides a list of the most aggressive dog breeds and also the least aggressive.
fortheloveofthedogblog.com/news-updates/the-most-aggressive-dog-breeds-dachshund-1