The German Shepherd Dog (GSD, also known as an Alsatian), (German: Deutscher Schäferhund) is a breed of large-sized dog that originated in Germany. German Shepherds are a relatively new breed of dog, whose origins date to 1899. As part of the Herding group, the German Shepherd is a working dog developed originally for herding sheep. Because of their strength, intelligence and abilities in obedience training they are often employed in police and military roles, in forces around the world. Due to their loyal and protective nature the German Shepherd is one of the most registered of breeds. Shepherds were bred specifically for their intelligence, a trait for which they are now renowned. They are considered to be the third most intelligent breed of dog, behind Border Collies and Poodles. In the book The Intelligence of Dogs, author Stanley Coren ranked the breed third for intelligence. He found that they had the ability to learn simple tasks after only five repetitions and obeyed the first command given 95% of the time. Coupled with their strength, this trait makes the breed desirable as police, guard, and search and rescue dogs, as they are able to quickly learn various tasks and interpret instructions better than other large breeds. German Shepherds have a reputation for aggression and have been banned in some jurisdictions as a result. In the United States, German Shepherds are responsible for more random bitings than any other breed, and have a known tendency to attack smaller breeds of dogs. Reports have found that statistically German Shepherds are the breed third most likely to attack a person. Another report found that German Shepherds accounted for almost half of the dog bites that required medical attention. These claims have been refuted on the basis that German Shepherds represent a higher proportion of the population than other breeds. However, reports indicate that Shepherds are over-represented when the statistics take into account the difference in population. German Shepherds are highly active dogs, and described in breed standards as self-assured. The breed is marked by a willingness to learn and an eagerness to have a purpose. Shepherds have a loyal nature and bond well with people they know. However, they can become over-protective of their family and territory, especially if not socialized correctly. An aloof personality makes them approachable, but not inclined to become immediate friends with strangers. German Shepherds are highly obedient and not easily distracted, but due to their strong self-will must be trained by "a firm hand".