Optiver Quantitative Researcher interview questions

3 weeks after submitting an online application, I received an email to complete an online test. This was a SHL mental aptitude test with 30 questions - 3 minutes per question. Couple of days later, I recieved an invitation for a telephonic interview with a recruiter. This was motivational + competancy based. Two days later I recieved an invitation for on-site interviews. There were three interviews: 1) Interview with a recruiter: motivational + competancy based questions 2) Technical interview: puzzles + probability based questions 3) Technical interview: puzzles + probability based questions

I had a phone interview only and there is no much to tell about it. Regular general questions about experience, reasons to leave, etc. The main complaint is about process in general. I managed to check the status of my job application and get a phone call only after 1+ month using LinkedIn as a primary communication method, contacting directly the head of HR department because they did not reply to the emails. After that I was informed that they would make a decision regarding the 2nd technical interview within 2 week. After 3 weeks waiting I contacted directly the HR person who conducted the interview using LinkedIn again (they had not replied to my email again) and received a standard message about high number of applications. After 2 weeks I contacted Head HR again, they called me back on the next day informing that my application was not successful. I am sure that there was a high workload at that moment, and completely understand that. However, as far as I can see, my case is not the first one and I would prefer be informed about estimated time to wait in advance.