Brain Snacks: Tasty Tidbits of Knowledge
The critics Mike Tierce and John Michael Crofton believe that Arnold Friend is modeled on Bob Dylan. Citing Dylan's song "Mr. Tambourine Man," they argue that Friend represents a disruptive creative force that isn't necessarily "evil" or "Satanic" (source). You might have noticed that the story is also dedicated to Dylan.
Joyce Carol Oates has also published mystery novels under the name "Rosamond Smith" (source).