Pinterest Data Scientist Interview Questions
Master your tech interview with our curated database of real questions from top companies.
Measure Billboard Campaign Impact: Design, Bias, Test Strategy
Measuring Billboard Impact on Brand Awareness Scenario A marketing team launched billboard ads in several cities and wants to estimate the campaign's ...
Clean and Aggregate Transactions for Finance Dashboard
transactions id | user_id | amount | timestamp | category 1 | 1001 | 19.99 | 2023-01-01 09:00:00 | grocery 2 | 1001 | 5.50 | 2023...
Investigate Homepage Experiment Without Control Group: Methods and Metrics
Scenario A social-media homepage team is running experimentation and product-metric analyses on a personalized feed. An intern accidentally launched a...
Evaluate New Feed-Ranking Algorithm with A/B Testing
Experiment Design: New Feed-Ranking Algorithm and Daily Active Minutes Scenario A social-media platform plans to evaluate a new feed-ranking algorithm...
Implement Binary Search for Policy Violation Logs
violations +--------+---------+---------------+ | pin_id | type | violation_date| +--------+---------+---------------+ | 0 | spam | 2022-01...
Assess Cultural Fit Through Behavioral Interview Questions
Behavioral and Leadership Interview Prompts — Data Scientist (Onsite) Context You are interviewing for a Data Scientist role with cross-functional sta...
Determine Appropriate Statistical Test for Comparing Means
A/B Test: Active Minutes After Two Weeks Scenario You ran a two-week A/B experiment on a new algorithm. The primary metric is user active minutes. Ass...
Analyze Global Engagement and Impressions with SQL Queries
impressions +---------+---------+----------+----------------+ | user_id | country | category | impression_cnt | +---------+---------+----------+------...
Calculate 95% Bootstrap Confidence Interval for Order Values
Scenario An e-commerce firm wants a 95% confidence interval for the average order value but only has a single historical sample of order amounts. Ques...
Optimize Hyper-parameter Search to Prevent Combinatorial Explosion
Enumerate Grid-Search Hyperparameter Combinations and Manage Explosion Context You are building a hyper-parameter optimization service that must enume...
Implement Data Structure for Top-K Elements in Streams
Scenario Analytics feature that must constantly report the K largest numbers seen so far. Question Implement a data structure that ingests a stream of...
Implement DelayQueue with Idempotent Task Execution
Scenario Message broker offers DelayQueue where tasks execute at future timestamps, ensuring idempotency on duplicate IDs. Question Implement a delay ...
How to Design a Proportional Randomized Sampler?
Scenario Randomized promotion engine must pick an item proportional to its score, but scores have no upper bound. Question Design a sampler pick() tha...
Design Algorithm to Minimize Payments in Expense-Sharing App
Scenario Expense-sharing app needs to settle debts among friends after a trip. Question Given a list of transactions (payer, payee, amount), design an...
Maximize Non-Overlapping Task Scheduling Efficiency
Scenario Job scheduler on a single machine wants to maximise throughput. Question Given tasks with [start, end) times, return the maximum number of no...
Determine Pin Connections Through Common Boards
Scenario Pinterest boards contain many pins; need to infer relationships between pins. Question Given the membership lists of all boards, write a func...
Estimate Highway Billboard Impressions Using Traffic Data
Estimating Billboard Reach and Impressions Scenario An out-of-home (OOH) advertising team wants to estimate both reach (unique people who saw the ad a...
Assess Cultural Fit and Self-Reflection in Hiring Process
Behavioral & Leadership Interview — Data Scientist (Onsite) Context The interviewer is assessing cultural fit, ownership, customer focus, and your abi...
Implement LRUCache with O(1) Operations and Thread Safety
Scenario High-traffic API needs constant-time eviction cache. Question Implement an LRUCache supporting get(key) and put(key,val) in O( 1). Describe ...
Decode and Explain Ambiguity in Compression Strings
Scenario Compression library that encodes an array as count-value pairs where value is one digit but count may be many digits. Question Implement deco...