"Did I hear the phone ringing?"
"Yeah, several times."
Don waited for Charlie to realize he wanted more information.
"Uhhh, once was Dad, calling to say he's going to stay with Aunt Jean. Apparently that quick-fix to her water heater wasn't so quick. And a few were wrong numbers to my cellphone."
Don had been hoping that Terry would call about her presentation. Not that he was holding his breath or anything.
"There are some cookies from Amita in that plastic container of the fridge," Charlie called over his shoulder.
Don snagged the cookies and followed him to the garage. "Amita made you cookies?"
The surprise in his voice made Charlie self-conscious and he dropped behind his desk to plug in an electric fan. "She didn't make cookies for me," he amended. "She made cookies. And I couldn't just leave them at school."
"Oh, no?" Don said innocently, swallowing a cookie.
"I'd never get rid of Larry if he found out I kept cookies in my office."
That made Don laugh and Charlie was glad to see him relax a little.
"If you're turning your investigative powers on me," he said "can I assume nothing much happened at work?"
Don took the glass Charlie was offering and propped his feet up on a stack of textbooks. "Mental Health Enrichment Seminars," he sighed, "What to do if your suspect turns out to be psychotic, instead of just plain crazy like most of the people who tangle with the FBI. Is it wrong to hope that a major financial fraud case is discovered before the end of the week?"
"No worse than planning major financial fraud while sitting in faculty meetings," Charlie offered. "Honestly, if the faculty senate doesn't come to a conclusion on plus/minus grading pretty soon, I going to develop designs on the stock market." He paused when he caught Don's eyes. "That's a joke, Don. I'm kidding. I couldn't…that is…I would never…well, just forget it."
Don tried to make his face blank. He hadn't meant to look surprised, or accusing, or however he'd looked. He just couldn't turn his mind off after the day's lectures.
"So, uhm, Terry gives a presentation tomorrow," he said at last, just to break the silence. "She won't tell me what it's about. Only that it's 'interactive.'"
"Crime rates are supposed to go up in the summer," Charlie mused, refusing to comment on the seminars, "Ice cream-Rape Theorum and all that. Maybe you should enjoy the break while you've got it."
Don choked on his lemonade, spitting a cherry onto the floor of the garage. "Did you just say 'Ice cream–rape theorum?"
"Yeah—there's a statistical correlation between the number of rapes reported and the revenue of ice cream vendors in the LA County area. When one goes up, so does the other. I call it the Ice-Cream-Rape Theorum when I teach my intro classes."
"But that doesn't make any sense. There's nothing to link ice cream with rape."
Charlie raised his eyebrows, looking supremely innocent. "Obviously there is a link, otherwise, why such a close correlation? It's held consistent for years."
Don could see his brother smiling behind his lemonade glass. "Ok, Charlie, give me a hint."
"Well," Charlie reached for a cookie. "All I said was correlation. I didn't say it was causative."
Don thought about that one. "So something else is causing the rapes, other than the purchase of ice cream? Of course it is! Because ice cream has nothing to do with anything."
"No, no," Charlie relented in the face of Don's annoyance. "Think about it the other way around. Not what causes the crime, what causes ice cream consumption. Why would people buy ice cream from a street vendor?"
"Uhm—because they like ice cream?"
Charlie just looked at him, so Don kept guessing. "Because it's warm outside?""Right. It's summer, people are wandering around, tourists…"
"Maybe in neighborhoods they don't know really well, later in the evenings 'cause it's still light," continued Don, "Just having a good time…not really thinking about safety…"
"Not exactly wearing winter coats and mittens," Charlie threw in.
"So, the increased number of people buying ice cream and the jump in reported rapes are unrelated results of the same cause?"
"Exactly," Charlie smiled, "And that cause is…"
"Summertime," Don concluded.
"I use it every year, just about, to teach my students that context is what makes numbers meaningful. Take them out of context and you can make them say anything, even the wrong thing. For instance, there's—"
"Charlie," Don interrupted, "do you hear voices?"
Charlie stopped for a minute, confused, "No. Dad's not coming home tonight, remember, he's going to drive back tomorrow. We're the only ones here."