I applied through university. The process took 1 day. I interviewed at Chicago Trading Company (Chicago, IL) in Apr 2015
Interview
Interview on campus - first round. There were some quick mental math questions, some questions about trading, and about my interest in market making. I didn't have many good answers for these questions and honestly wish I was more prepared. Also I'd recommend that you brush up on mental math before going into the interview. Review probability, expectations, multiplication, basic stuff that they test you on.
I applied in-person. The process took 1 week. I interviewed at Chicago Trading Company in Feb 2018
Interview
Received an assessment for 126 questions in 20 mins. Was not too bad all quick math and a lot of vocabulary. Not really a way to prepare for it other than brushing upon vocabulary.
I applied online. The process took 4 weeks. I interviewed at Chicago Trading Company (Chicago, IL) in Oct 2017
Interview
Online test followed by a recorded interview, On campus interview, and then super day in Chicago. Questions are part brain teasers, part behavioral, and part mental math. If you get to the super day, there is a mock trading exercise.
I applied online. The process took 4 weeks. I interviewed at Chicago Trading Company in Oct 2017
Interview
Applied online. Assessment test with 126 questions and only 20 minutes, followed by a virtual cover letter and then an on campus interview. Didn't get called for the final round in Chicago