David Franklin Quotes

For these ‘future leaders’ in the classroom, it is more important to understand the psychology of certainty. Often, we believe what we want to believe. Dan starts with an example of the 2016 Presidential Election in the United States. He asks the question: “Relative to what you expected to happen, how surprised were you when you learned that Trump had won the election?

What is the probability that at least two people in a group of 20 people will have the same birthday?

An American student, well-versed in U.S. politics, puts his hand up. He says he had been following Nate Silver’s ‘Five Thirty-Eight’ website, which had said that Trump only had about a 30% chance of winning the election.

Dan asks the class whether any of them has ever checked the weather on their phone to see if it’s likely to rain while they’re outside. Everyone has. “What do you do if you see there’s a 30% chance of rain?” “Take an umbrella”, several students all say at once.

Dan’s use of two-stage exams kills two birds with one stone. Firstly, he maximises learning by ensuring that the exam itself is a learning experience. Second, in doing so, he makes clear that the grade is less important than the learning. Two-stage exams have not yet ‘taken off’ around the world, and grades remain the key outcome of most exams for most students. Dan, though, has taken advantage of his position in a graduate university environment to push the idea forward.

With 80 people, the size of this classroom, the probability that there will be no shared birthdays is so tiny as to be virtually impossible.

Dan’s goal, taken from his mentor Richard Zeckhauser, is to get students to think probabilistically about the world. This means engaging with the challenge of understanding and accepting what 29% means in the context of a Trump victory, and fighting the brain’s natural inclination to see things in binary terms.