The committee calls the winners before announcing the names to the world each year. It's always a decent hour in Stockholm -- the middle of the day -- but that means it is the middle of the night on the US West Coast.
But Milgrom couldn't be reached, so his neighbor -- and fellow prize winner -- Robert Wilson stepped up and walked over to Milgrom's house.
In a security camera video recording, Wilson is seen ringing Milgrom's doorbell at 2:15 a.m. PT and knocking for several seconds. Finally, Milgrom responds.
"Paul, it's Bob Wilson," Wilson says. "You've won the Nobel Prize. And so they're trying to reach you, but they cannot. They don't seem to have a number for you."
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"We gave them your cell phone number," Wilson's wife, Mary, says.
A moment of silence follows.
"Yeah, I have? Wow," Milgrom responds from the other side of the door.
"Will you answer your phone?" Wilson's wife asks with a laugh.
Milgrom's wife was in Stockholm. Because she received a notification from the doorbell security camera back home, she got to watch as Wilson relayed the good news, according to a tweet from Stanford University.
Milgrom and Wilson, both professors at Stanford University, received the prize for their work in auction theory.
The professors "used their insights to design new auction formats for goods and services that are difficult to sell in a traditional way, such as radio frequencies," the Royal Swedish Academy of Sciences said in a statement.
"Their discoveries have benefited sellers, buyers and taxpayers around the world."
It's not the first time the call from Stockholm has been missed by an American winner.
In 2010, Martin Chalfie won the Nobel Prize in Chemistry along with Osamu Shimomura and Roger Y. Tsien, but he slept through the call.
"I woke up at ten after six, and I realised that they must have given the Prize in Chemistry, so I simply said, 'Okay, who's the schnook that got the prize this time?," Chalfie said in a conversation with a Nobel.org representative that the Nobel Committee posted online. "And so I opened up my laptop, and I got to the Nobel Prize site and I found out I was the schnook!"
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