Observational learning is the learning that occurs through observing the behavior of others. This form of learning does not need reinforcement to occur; instead, a model animal is required. While the model may not be intentionally trying to instill any particular behavior, many behaviors that are observed are remembered and imitated. The domestic dog is a social species and its social dependency makes it aware of the behavior of others, which contributes to its own behavior and learning abilities. There is, however, ongoing discussion about how much, and how, dogs can learn by interacting with each other and with people.
Discourage him from biting or nipping. Instead of scolding him, a great way to put off your mouthy canine is to pretend that you're in great pain when he's biting or nipping you. He'll be so surprised he's likely to stop immediately. If this doesn't work, try trading a chew toy for your hand or pant leg. The swap trick also works when he's into your favorite shoes. He'll prefer a toy or bone anyway. If all else fails, break up the biting behavior, and then just ignore him.
By now your dog is figuring out that “good things come to those who wait” and is starting to work on impulse control without being told. At this point in training, your dog has also figured out that obedience is The Strategy to get what he wants. This empowering realization means your dog understands he can take charge and control the situation to get the outcome he wants, overcoming some of the basic instincts that used to guide his behaviors. x
Lindsay says of this study, "Schilder and Van der Borg (2004) have published a report of disturbing findings regarding the short-term and long- term effects of shock used in the context of working dogs that is destined to become a source of significant controversy ... The absence of reduced drive or behavioral suppression with respect to critical activities associated with shock (e.g., bite work) makes one skeptical about the lasting adverse effects the authors claim to document. Although they offer no substantive evidence of trauma or harm to dogs, they provide loads of speculation, anecdotes, insinuations of gender and educational inadequacies, and derogatory comments regarding the motivation and competence of IPO trainers in its place." 
Training a dog to sit, lie down, stay, and come when called make your job as a pet parent easier, but they can also make your dog’s life better and safer. Knowing these commands can help you protect your dog from dangerous situations, and in some cases, save his life. Once you’ve learned how to properly teach your dog, training will be a fun and useful activity for you both.
A year-long study by the University of Pennsylvania, published in the journal Applied Animal Behavior Science (Elsevier), showed that aggressive dogs who were trained with aggressive, confrontational, or aversive training techniques, such as being stared at, growled at, rolled onto their backs, or hit, continued their aggressive ways. Non-aversive training methods, such as exercise or rewards, were very successful in reducing or eliminating aggressive responses.