Uber — AI Research Scientist ❌ Failed
Level: Unknown Level
Round: Phone Screen · Type: Coding, Technical Discussion · Difficulty: 7/10 · Duration: 60 min · Interviewer: Unfriendly
Topics: Algorithms, Experiment Design, Metrics, A/B Testing
Location: San Francisco, CA
Interview date: 2025-12-31
Got offer: False
Summary
Round 1: Coding
Question: LeetCode reverse array rotation with follow-up. I provided two solutions, one correct and one with a minor bug.
Round 2: Experiment Design
Question: Designed an experiment to explore the relationship between ETA and session rider conversion, focusing on switchback methods instead of A/B testing.
Round 3: Production & Rollout
Question: Discussed the rollout of the experiment into production, including designing treatment buckets (multiplier), rollout guardrails, and various variable designs. Also, I addressed the interpretation of experimental results with 95% confidence intervals.
Details
Preparation Tips & Key Takeaways
What I Learned
- The importance of speed, accuracy, and depth of understanding of metrics, especially for economics-related questions.
- The need to clearly and concisely explain experiment designs and interpret results under time constraints.
- Focusing on ratios of variables, rather than individual variables, is crucial in this context.
Recommended Preparation
Coding Practice
- Practice array manipulation algorithms and related follow-up questions on platforms like LeetCode.
Experiment Design
- Study different experimental designs, including A/B testing and switchback methods.
- Focus on the relationship between key performance indicators (KPIs) and how to design experiments to measure them effectively.
Metrics Analysis
- Review statistical concepts like confidence intervals and their interpretation.
- Prepare to explain the rationale behind various design choices and their implications.
Resources I Recommend
- Use ChatGPT to expand on specific topics and generate examples for practice.
- Review economics principles related to metric analysis and experimental design.
Common Pitfalls to Avoid
- Speed is crucial; practice explaining experiment designs quickly and accurately.
- Ensure a deep understanding of metrics and their implications for experimental design.
LeetCode similar: LeetCode 189