I applied online. I interviewed at Susquehanna International Group in Jan 2018
Interview
I had three quantitative interviews, then a full on-site interview. Mostly math/probability questions that are rather creative, but they also asked a little statistics and pseudo-coding. You don't need to know much about financial markets.
Interview questions [1]
Question 1
Probability and knowing a little game theory helps too.
I interviewed at Susquehanna International Group (Philadelphia, PA)
Interview
The first hurdle in SIG’s interview process is an online assessment administered through Mercer | Mettl. It tests knowledge in mathematics, probability, and statistics. The assessment combines puzzles and probability questions, along with topics like expected value, combinatorics, and logic. Overall, it follows the standard quant interview format — probability and statistics are the most critical areas to master before sitting the test.
An online math test testing topics such as probability theory, basic logics and word problems that you need to do in a relatively short time. I was not invited for further interviews
General question such as background and motivation then 2-3 math questions based on probability and expected value. Difficult than OA. But overall, it is managable if you have done a proper review.