I applied through a recruiter. The process took 2 months. I interviewed at TikTok (Seattle, WA) in Aug 2021
Interview
Recruiter screen > tech screen > tech interview > tech interview > recruiter screen
Tech screen: SQL and metric movement product sense.
Other tech interviews: product sense about metric movement, how to interpret metrics, intermediate SQL, product sense about how to create a funnel for a product and determine highest impact work based on that, very very similar to FB data scientist interview.
Interviewers were polite but extremely professional - hard to get a sense for wlb there but it seems like it was standard to work 10 hr days, and it could get much busier. Majority of decision making is offshore. Recruiters play hardball.
Interview questions [1]
Question 1
SQL impressions per video type questions, ranking via window functions, lots of product sense questions.
A former colleague referred me to the Data Scientist position at TikTok, which kicked off the interview process. The technical screen included a question about designing an A/B test for a ranking model, followed by an SQL challenge related to user sessions. The funny part was that the SQL problem was a twist on one I had been grinding through on PracHub just a few days prior. After some behavioral interviews, I received an offer, but ultimately decided to decline as it didn't align with my goals.
Interview questions [2]
Question 1
Walk me through how you'd design an A/B test for a new ranking model on the For You feed, and how you'd pick guardrail metrics.
Given a sessions table (user_id, session_start, session_end, country), write SQL to find the users whose average session length grew the most week-over-week.
I applied online. I interviewed at TikTok (London, England)
Interview
one medium level sql test and an open question
Since i'm not familiar with business context(though i actually spent time preparing AB test and causal inference), i didn't get what i should answer.
Interview questions [1]
Question 1
if tiktok shop is going to launch in Netherland, how to evaluate it before AB test