I really wish you provided the research study. I would be happy to answer. It should be attached to wherever you found this question. Hope this helps :)
Depending on the spread of the bloodstain.
Blood stain that spread in large distance within small pebbles usually indicates a hard force such as blunt weapons attack or bullets
If the bloodstain is gushing down like a pool, it indicates a stabbing incidents using sharp objects.
The answer is although Faulkner WENT TO school when he was young he did like to read. He, therefore, educated himself.