At one point Chris Schenkel mentions the "red and white" in reference to Ohio State. Anyone who was ever near Columbus (or followed the Ohio State-Michigan rivalry) knows that the colors are "scarlet and gray". (The incorrect "red/white" reference to the Ohio State Buckeyes comes from Philip Roth's book itself; see in Chapter 7, page 104, line 7 from the top [Houghton Mifflin Co. edition, 1959].)
At the dinner table, Julie is told that it is earlier in Columbus, where Harriet is calling from, than where she lives in New York. In fact both cities are in the same Eastern Standard Time Zone. In the book, Harriet is calling from Milwaukee in the Central Time Zone, which is correct. However, when the screenplay changed her location to Columbus, the writer failed to realize this fact and change the dialog or the city.