What literary allusion does melinda mention in spring break?

In Laurie Halse Anderson's novel "Speak," Melinda mentions the literary allusion to "The Scarlet Letter" by Nathaniel Hawthorne during spring break when she attends a party at Rachel's house dressed as Hester Prynne from the novel. This allusion highlights Melinda's feelings of alienation and parallels her own experiences with the protagonist of "The Scarlet Letter."