Itaú Unibanco Data Scientist Interview Questions
& Process

The interview started with a team chat where they talked about my background and the job's challenges. I passed that. Then came an online test based on a syllabus they provided. I studied for it, and the coding questions were mostly solvable with SK-Learn, though some were confusing with multiple correct answers. I passed that too. The next part was a Q&A interview that turned out to be a nightmare. Three interviewers, one woman who was really mean and arrogant, another nice guy, and a third who just typed the whole time. The woman told me I couldn't look at anything and that not knowing an answer wouldn't mean failing. Her questions were hard to understand, and the nice guy had to help clarify. She interrupted me rudely when I was answering. She got upset when I explained that 100% accuracy in fraud detection is impossible due to overfitting and that we'd need to define false positive/negative rates with the business team. The interview ran over by 30 minutes. I failed and was told I couldn't explain linear regression or understand models, despite being a lecturer and having a master's in DS. It felt like she would fail anyone she didn't like. This process felt unethical and biased.

A recruiter reached out via message to schedule an interview for the Customer Support team. I first checked if the position was strictly for a senior role or if it could extend to higher levels like Tech Lead or Specialist. After waiting a week, the recruiter clarified that while the position was specifically for a Senior Data Scientist, I could potentially function as a Tech Lead within that Senior role. This was confusing, so I asked for clarification. The recruiter explained that in some roles, an individual leads the team technically, contributes to architectural decisions, and supports the team, but their formal title remains Senior. I found this suggestion peculiar, as it seemed like a potential trap: either I'd be paid as a Senior but perform more duties than allowed by labor laws, or I'd be paid as a Tech Lead but hold a Senior title. Since both scenarios sounded odd, I inquired about the salary range for the position but received no response. Subsequently, I got an email stating I was eliminated from a process I hadn't even confirmed participation in.

It started with an online quiz that was mostly about my academic background. Then, I had an online practical exam that included regression, clustering, and classification models using synthetic data, along with theoretical questions. After that, a technical interviewer discussed my exam answers, asking for details on my process and offering suggestions. This was followed by a video call with the hiring managers to get to know me better. Finally, I received a job offer.