"On the contrary. I have determined the optimal gift based on her personality matrix, historical satisfaction data, and current market value. I’m giving her a signed photograph of Carl Sagan."
Long pause.
Missy stares at it. Her face does the thing Sheldon cannot read—a wobble between confusion and something softer.
Sheldon applies statistical probability to gift-giving, with predictably disastrous results for Missy’s birthday.
(from the hallway, eavesdropping): "I hate you."