Revealing mistake: In an early shot shown from the neighbor's house, it is established that the Spencers' house is quite a ways uphill. Some of the later shots where Claire is spying on her neighbors and looking at their home, the angle of view does not appear to be correct. The neighbors' house looks like it's a lot closer and more level with the Spencers' home.
Revealing mistake: After Claire and Norman drop their daughter off at school, that night, Norman is in bed with his laptop, typing, but not once do his fingers touch the space bar.
Answer: They are the initials of Madison Elizabeth Frank, the woman Norman was having an affair with and later killed.
raywest ★