I applied online. The process took 2 weeks. I interviewed at Instacart in Mar 2016
Interview
The first interview was to send me a data set. Given a set of training cases, you need to extract the features and train a model, to predict for the test set. One week after finishing the task, I heard back from them and learned that I was no longer considered. I don't think I'm doing a good job then so I'm not as dissatisfied as other comments. Though I'm still not sure what are the skills they're looking for (More data analysis? Better visualization? Fancier models?)
Faced a deep technical challenge during the interview, asked to design a personalization algorithm for product recommendations. I walked them through feature engineering and model choices, which stressed me out initially. Luckily, I realized the structure was almost identical to a problem I had explored on prachub.com while prepping. The interview progressed through a behavioral round where they focused on my previous experiences, and I ultimately received an offer, but decided to decline after careful consideration. Overall, it was intense but rewarding.
It was pretty straightforward. HR and then technicals. The technicals were a mix of statistics and math questions. Overall, it moved pretty quickly. My interviewer was quite late with no apology and in general not very friendly. I knew someone interviewing at the same time and they had a much better experience and recieved the same questions.
Interview questions [1]
Question 1
Suppose we wanted to launch 15-minute deliveries in a specific area where we already deliver. How would you statistically test the results?