Square Data Scientist Interview Questions

The questions to prepare for a Square Data Scientist interview. Questions from real interview reports rank first. Updated weekly.

7-Day Rolling DAU on Facebook

Hard

Compute daily distinct active users and a 7-day rolling average using a CTE and window function.

Square

More SQL & Data Manipulation questions with a free account

More Behavioral & Leadership questions with a free account

Diagnose Sample Ratio Mismatch

Hard

Investigate sample ratio mismatch and decide whether an experiment readout is trustworthy enough to ship.

Guardrail MetricsSample Ratio MismatchA/B Testing

Square

More A/B Testing & Experimentation questions with a free account

Coin-Flip Expected Value

Medium

Tests probability modeling and simulation-based reasoning in Python.

simulationExpected ValueConditional Probability

Square

More Statistics & Probability questions with a free account

Create a free account to unlock this list and practice real interview questions.

Predict Customer Churn

Medium

Build a churn model that flags at-risk customers early using behavioral, billing, and support signals.

Feature EngineeringModel EvaluationSupervised Learning

Square

Primary Metric for Crypto Flow

Medium

Tests product sense and metric design tied to user outcomes for Square’s crypto feature.

Metricsonboardinguser value

Square

Clean Memos to Merchant Codes

Medium

Tests NLP preprocessing, normalization, and practical data cleaning for transaction classification.

data preprocessingText ClassificationTokenization

Square

Open any question for its full solution and discussion.