The character Vern (Peter's social worker) is based on the character Vern (played by Micheal D. Roberts) in Rain Man (1988). In this film, Vern is a supportive worker at Raymond's (Dustin Hoffman) asylum, and says the line "I'm your main man Raymond, I'm your main man."
The MacArthur Fellowship (genius grant) selection process does not entail any sort of aptitude test. A confidential and anonymous panel nominates candidates who are evaluated on originality of past performance and potential for future advancements in their field.