Suppose a large dog food company has a new prototype that is supposed to prolong the life of dogs.
The company randomly selects two groups of $100$ dogs each: one group will be fed this new food for the duration of their entire lives; the other group will be fed the leading competitor’s brand of dog food.
Variables such as exercise, location, and medical treatment are all controlled for. However, the company needs to decide whether to use only a specific breed of dog or include a variety of dogs.
What is a statistical advantage of using only one specific breed of dog for this study? A statistical disadvantage?