J'ai postulé en ligne. Le processus a pris 2 semaines. J'ai passé un entretien chez Jane Street (Londres, Angleterre) en sept. 2024
Entretien
1st interview: basic probability brainteasers
2nd interview: significantly more difficult game questions one involving dice and other coins. Two players roll a dice then decide whether they pick their own, other, or withhold decision until next round. What's the optimal strategy?
Questions d'entretien [1]
Question 1
You are playing a game where you flip a coin 5 times. You win if three heads come up in the 5 coin tosses. You lose if three tails come up in the 5 coin tosses. If you win you get £1. If you lose you lose £1. Before each flip you can choose to either double the stakes from their previous value (if you win you get £2n and if you lose you lose £2n where n is the amount you get if you win beforehand) or keep them the same. Are you willing to pay £0.50 to play this game?
Flipping coins, betting on sums, products, other interesting contracts. Some amount of being smart about formulating a market making strategy. Finally, some game theory (nash equilibrium) and excel tasks. Overall very thorough and comprehensive.
J'ai postulé en ligne. J'ai passé un entretien chez Jane Street (Hong Kong) en juin 2023
Entretien
They asked entirely maths/probability questions, usually with some sort of coin toss/die roll element in the context of a game. Very friendly and patient interviewers, who will guide you through the questions.
Questions d'entretien [1]
Question 1
We are playing a game where we roll two die. If the sum is even, you win and the game ends. If the sum is 7, I win and the game ends. If the sum is odd, we roll again. What is the probability that you win?