The person responsible for the study: John B. Watson was an American psychologist known for his work in the field of behaviorism. 

Background information: The Little Albert experiment was conducted to test classical conditioning, a concept familiarized by Ivan Pavlov, by testing the idea with dogs and ultimately extending those results to reveal behaviors in humans. 

Methodology: Watson brought in Little Albert, an 11-month-old infant who presented no fear of rabbits whenever one was brought near him. However, researchers found that by pairing the white rat with a loud, scary noise, Albert began to associate the rat with the frightening noise every time it was brought in. The same results remained consistent with other animals and even objects. 

Results: The experiment showed how, through classical conditioning, humans can be conditioned to fear. 

Significance of results/legacy/recent relevance: 

This experiment was highly famous in the history of psychology and was pivotal in understanding how emotions such as fear can be learned through conditioning. In addition, it provided evidence for behaviorism, a philosophy that prioritizes the importance of environmental stimuli in manipulating behavior. 

How to improve the experiment: 

While the study successfully achieved its purpose, it could be improved to uphold ethical standards. This can be done by desensitizing the child after the study to ensure that he is no longer afraid of the animals and objects used throughout the study.