Solo, against an interviewer who knows the answer

Interview practice

This is the market-making game quant firms actually play in interviews. You get a question, you make a market, and the interviewer, who has a pretty good idea of the answer, trades against you. Your job is to read what they're doing and let it move your price.

Difficulty
Questions
Length

Before you start

How it works

  1. You get a question with a number for an answer, like "how tall is the Burj Khalifa?".
  2. You make a market: a bid (where you'd buy) and an ask (where you'd sell), plus a size.
  3. The interviewer trades: they buy your ask if they think the answer's higher, sell your bid if lower, or pass.
  4. You adjust. The interviewer knows roughly what the answer is and trades to make money off you. If they keep buying, the answer's higher, so move up. That's the whole skill.
  5. Watch for announcements. Part-way through you might get a clue: a related fact to reason from, never the answer. On Hard it can also be a change to what the market settles on (say, 70% of the answer). Re-price straight away.
  6. At the end everything settles at the true answer and you get a grade and a proper debrief.

New to this? Read the guide. It takes ten minutes.