Giving confidence intervals on interviews

I have interviews coming up with Optiver, Virtu, Jane Street, etc.. These companies like to ask candidates for confidence intervals for their answers. While this usually not too difficult to do, I'm curious about what interval to give if I'm certain of my answer. Let's say I'm asked to determine the sum of the integers from 1 to 100, which I know to be 5050, do I say [5050,5050] is my confidence interval or do I give a wider range, so I don't seem "overconfident"?

2 Comments
 

If it's that simple of a question and you really are that confident in your answer, feel free to say [5050, 5050] as your answer. I only ever got asked for confidence intervals when the thing wasn't as exact (i.e. what's the current temperature outside, what will it be at midnight tonight, what's the population of Chicago).

 

Voluptatibus corporis voluptas natus aut totam quia. Possimus animi accusamus eaque voluptate qui quis praesentium.

Voluptas sapiente at eius at dignissimos eveniet deserunt. Possimus nam autem doloremque quo similique. Eligendi quidem soluta reiciendis numquam qui voluptatem.

Eius provident nulla id molestiae. Placeat molestiae eaque eos esse dolore itaque tempora. Est in architecto voluptatum et doloremque quis sed. Vel praesentium deserunt adipisci quas rerum neque tempora.

Career Advancement Opportunities

November 2026 Investment Banking

  • Evercore 01 99.5%
  • Moelis & Company 01 99.0%
  • JPMorgan 01 98.4%
  • Guggenheim Partners 02 97.9%
  • Morgan Stanley 06 97.4%

Overall Employee Satisfaction

November 2026 Investment Banking

  • Moelis & Company No 99.5%
  • Morgan Stanley 02 99.0%
  • Evercore 01 98.4%
  • Banco Santander 02 97.9%
  • BMO Capital Markets 13 97.4%

Professional Growth Opportunities

November 2026 Investment Banking

  • Evercore 01 99.5%
  • Moelis & Company 01 99.0%
  • Morgan Stanley 05 98.4%
  • Goldman Sachs 01 97.9%
  • JPMorgan No 97.4%

Total Avg Compensation

November 2026 Investment Banking

  • Vice President (16) $429
  • Associates (57) $264
  • 3rd+ Year Analyst (8) $210
  • 2nd Year Analyst (28) $184
  • Intern/Summer Associate (16) $161
  • 1st Year Analyst (84) $151
  • Intern/Summer Analyst (76) $101
notes
16 IB Interviews Notes

“... there’s no excuse to not take advantage of the resources out there available to you. Best value for your $ are the...”

Leaderboard

success
From 10 rejections to 1 dream investment banking internship

“... I believe it was the single biggest reason why I ended up with an offer...”