Jane Street Quant Interview Questions
In this article, we will delve into three real-world quant interview problems, providing step-by-step solutions, detailed explanations of concepts involved, and practical insights into optimal strategies.
There are two players, A and B. A 30-sided die exists with faces numbered from 1 to 30. Player A chooses a number \( a \) first, then Player B chooses a different number \( b \). The die is rolled. Whoever chose the number closer to the outcome wins an amount of money equal to the die roll. If the die lands exactly halfway between the two numbers, a predetermined tie-breaker (e.g., the lower number wins) can be assumed if necessary.
For example: If A chooses 9, B chooses 10, and the die rolls a 7, then B pays A $7.
This is a game theory problem involving optimal choices and expectations. The key is to determine the best strategy for both players and compute the expected value for each.
