Cvs Health Interview Questions
Practice the exact questions companies are asking right now.
Use pandas to aggregate, pivot, and label
Given two pandas DataFrames, write code to: (1) merge and aggregate revenue; (2) produce a 2x2 pivot; (3) compute per-state counts with value_counts, ...
Implement R² and Compare PCA With/Without Scaling
NumPy-only implementation: R² and PCA (Data Scientist take-home) Implement from scratch using only NumPy (no scikit-learn). Use float64 throughout and...
Explain Causal-Inference Techniques in Your Machine Learning Project
Technical Deep-Dive: ML Project With Causal Inference Prompt Walk me through one machine-learning project you led and explain any causal-inference tec...
Build a leak-free sklearn churn pipeline
Take‑Home ML Task: Reproducible Subscription Classification Pipeline You are given a daily user-level dataset and must build a reproducible Python (sc...
Compute A/B significance, CI, and power
You run an A/B test for 7 days. Control A: 520 conversions out of 10,000 sessions. Variant B: 630 conversions out of 11,500 sessions. Use a calculator...
Create and query an e-commerce schema
PostgreSQL only. 1) Create these tables with appropriate types and constraints (choose minimal correct types): products(product_id PK, name NOT NULL, ...
Explain your top strengths concretely
Behavioral Prompt: Strengths, STAR Evidence, and 90-Day Application Instructions State your top one or two strengths most relevant to a Senior Data Sc...
Handle challenges in MMM/MMX
MMM Fragility Diagnosis and Remediation Plan (Weekly, 156 Weeks) Context You inherit a weekly Marketing Mix Model (MMM/MMX) with 156 weeks of data. Th...
Diagnose a failing campaign
Vaccination-Lift Experiment Triage Plan Context: You ran a randomized CRM experiment (e.g., email/SMS/push) to increase vaccination uptake. The overal...
Launch and measure a TV campaign
6-Week Linear TV Experiment to Increase Flu Vaccinations Design a 6-week linear TV campaign and its measurement plan to causally estimate incremental ...
Design an email flu-shot experiment
End-to-End Experiment Design: Email Campaign to Increase Verified Flu Vaccinations Context: You are designing a 30-day email campaign to increase veri...
Explain p-value and choose correct test
Technical Screen: P-values and Robust Two-Sample/Paired Tests Context: You are a data scientist evaluating healthcare interventions. Answer in clear, ...
Design classification under missingness and imbalance
30-Day Readmission Classifier: End-to-End Plan Context: You are building a binary classifier to predict 30-day readmission using claims and EHR featur...
Aggregate radiology spend and derive fiscal month
Using Python/pandas, complete the tasks below. Assume the following CSV-like input, where service_dt is object dtype and amounts may be negative (adju...
Compute age-band spend and YoY in Georgia
Using ANSI SQL only, answer the three parts below on the following schema and samples. Assume dates are YYYY-MM-DD, paid_amt can be negative (adjustme...
Lead structured response to accuracy incident
Incident Response Plan: Spike in Incorrect Payments for CA Users Aged 18–24 Scenario Since 00:00 today, the share of incorrect payments for users aged...
Tune classifier and compute key metrics
Payment Error Classifier — Evaluation, Thresholding, and Cost-Sensitive Design Context You built a binary classifier to flag incorrect payments (posit...
Test payment-accuracy lift with p-value and power
AB Test of Payment Accuracy (Two Proportions) Assume transactions in the two periods are independent and large enough for normal approximations. Defin...
Calculate annual percentages and YoY by cohorts
Answer both SQL and Python parts. Be precise about deduping and denominator choices. SQL schema (sample rows): orders order_id | user_id | order_date ...
Describe handling pressure and stakeholder conflicts
Behavioral/Scenario Questions for a Data Scientist — Technical Screen Answer concisely using STAR (Situation, Task, Action, Result) where relevant. 1....