Anthropic
AI safety and research company behind Claude, focusing on constitutional AI.
5 Rounds
~20 Days
Very Hard
The Interview Loop
Recruiter Screen (30 min)
Standard fit check, behavioral questions, and resume overview.
Technical Loop (3-4 Rounds)
Deep dive into domain knowledge, coding, and system design.
Interview Question Bank
Data Scientist
•
Behavioral
•
medium
Tell me about a time you had to trade off model performance or project velocity for safety, fairness, or rigorous evaluation.
#AI Safety
#Ethics
#Decision Making
Data Scientist
•
Behavioral
•
medium
Anthropic highly values Constitutional AI. How would you handle a situation where a Product Manager wants to push a feature that significantly increases user engagement but slightly degrades our core alignment metrics?
#Alignment
#Stakeholder Management
#Product Strategy
Data Scientist
•
Behavioral
•
medium
Tell me about a time you discovered a significant flaw in your own data analysis after you had already presented the results to stakeholders. How did you handle it?
#Integrity
#Communication
#Mistakes
Data Scientist
•
Behavioral
•
hard
Anthropic highly values safety. Describe a situation where you had to push back against a product launch or feature because of safety, privacy, or data quality concerns.
#Safety
#Conflict Resolution
#Values
Data Scientist
•
Behavioral
•
easy
Tell me about a time you had to communicate a complex statistical concept to a non-technical stakeholder, such as a policy expert or product manager.
#Communication
#Cross-functional
Data Scientist
•
Behavioral
•
medium
Describe a project where you had to work with highly ambiguous requirements and define the success metrics from scratch.
#Ambiguity
#Initiative
#Metric Design
Data Scientist
•
Behavioral
•
medium
How do you prioritize your research or analysis tasks when faced with multiple urgent requests from different model training and product teams?
#Time Management
#Prioritization
#Stakeholder Management
Data Scientist
•
Behavioral
•
medium
Tell me about a time you disagreed with a senior researcher or engineer about the interpretation of an A/B test result or model evaluation.
#Conflict Resolution
#Data-Driven
#Collaboration
Data Scientist
•
Behavioral
•
easy
Why Anthropic? What specifically about our approach to AI alignment, Constitutional AI, and safety resonates with your career goals?
#Motivation
#Company Knowledge
#Alignment
Data Scientist
•
Behavioral
•
easy
Describe a time you automated a tedious data process or evaluation pipeline that saved your team significant time.
#Impact
#Automation
#Engineering Best Practices
Data Scientist
•
Behavioral
•
easy
Tell me about a time you had to quickly learn a new machine learning framework, statistical method, or domain to solve a pressing problem.
#Adaptability
#Continuous Learning
#Problem Solving
Data Scientist
•
Behavioral
•
easy
Explain the concept of a p-value and a confidence interval to a non-technical product manager who wants to launch a new feature immediately.
#Statistics
#Stakeholder Management
Data Scientist
•
Behavioral
•
medium
Tell me about a time you had to push back on a product launch or feature release due to data quality or safety concerns.
#Integrity
#Communication
#Conflict Resolution
Data Scientist
•
Behavioral
•
medium
Describe a situation where you discovered a critical flaw in your own analysis after it had already been shared with stakeholders. What did you do?
#Accountability
#Intellectual Honesty
Data Scientist
•
Behavioral
•
medium
How do you prioritize which research directions or metrics to focus on when evaluating open-ended model capabilities?
#Prioritization
#Ambiguity
#Research Strategy
Data Scientist
•
Behavioral
•
easy
Tell me about a time you had to communicate a highly complex statistical or machine learning concept to a group of software engineers.
#Cross-functional Collaboration
#Communication
Data Scientist
•
Behavioral
•
easy
Why do you want to work at Anthropic specifically, as opposed to other AI research labs like OpenAI, DeepMind, or Meta?
#Motivation
#Company Knowledge
Data Scientist
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Coding
•
medium
Implement a function in Python to calculate the Elo rating update for two LLMs given a human preference rating (win, loss, or tie).
#Python
#Math
#Algorithms
Data Scientist
•
Coding
•
medium
Write a Python function to efficiently deduplicate a massive dataset of text documents (billions of tokens) prior to model pre-training. What algorithmic approach would you use?
#Python
#Data Deduplication
#MinHash
#LSH
Data Scientist
•
Coding
•
medium
Given a table `claude_generations` with columns `user_id`, `prompt_length`, `generation_time_ms`, and `timestamp`, write a SQL query to calculate the 95th percentile latency for each user tier (join with `users` table) over the last 30 days.
#Window Functions
#Percentiles
#Performance Metrics
Data Scientist
•
Coding
•
easy
Write a Python script using Pandas to sample a stratified subset of 10,000 conversational logs, ensuring a balanced distribution across 5 different safety violation categories, while prioritizing longer conversations.
#Stratified Sampling
#Pandas
#Data Preparation
Data Scientist
•
Coding
•
hard
Implement an algorithm to find the longest common substring between two large text prompts. We use this to identify potential prompt injection templates spreading among users.
#Dynamic Programming
#String Manipulation
#Security
Data Scientist
•
Coding
•
medium
Given a table `user_interactions`, write a SQL query to find all users who have triggered the safety filter (`is_blocked = TRUE`) more than 3 times within any rolling 24-hour window.
#Rolling Windows
#Self Joins
#Anomaly Detection
Data Scientist
•
Coding
•
easy
Write a Python function to parse a large JSONL file of Claude's interaction logs and calculate the average response length in tokens for each prompt category.
#Python
#JSON
#Data Processing
Data Scientist
•
Coding
•
medium
Write a SQL query to calculate the rolling 7-day average of human preference win-rates for Claude 3 versus Claude 2, partitioned by the evaluation domain.
#SQL
#Window Functions
#Time Series
Data Scientist
•
Coding
•
hard
Given a dataset of prompt-response pairs with boolean safety violation flags from human annotators and a classifier's probability scores, write a script to compute the ROC-AUC score from scratch.
#Python
#ML Metrics
#Algorithms
Data Scientist
•
Coding
•
medium
Write a SQL query to identify the top 1% most active API users based on token consumption over the last 30 days, excluding internal Anthropic test accounts.
#SQL
#Percentiles
#Filtering
Data Scientist
•
Coding
•
medium
Implement a stratified sampling algorithm to select 10,000 prompt-response pairs for human evaluation, ensuring the sample exactly matches the real-world distribution of 15 different safety categories.
#Python
#Sampling
#Statistics
Data Scientist
•
Coding
•
medium
Write a Python function using NumPy to efficiently compute the cosine similarity between a single target embedding vector and a matrix of 1 million document embeddings.
#Python
#NumPy
#Linear Algebra
Data Scientist
•
Coding
•
medium
Given a table of human evaluations, write a SQL query to find the specific prompts that have the highest variance in human helpfulness ratings (indicating subjective or ambiguous prompts).
#SQL
#Aggregation
#Statistics
Data Scientist
•
Coding
•
medium
Write a SQL query to find the top 5% of users by token usage who have also triggered the safety filter more than 3 times in the last 30 days.
#Window Functions
#Filtering
#Aggregations
Data Scientist
•
Coding
•
hard
Given a table of user prompts with timestamps, write a SQL query to group these prompts into 'sessions'. A new session starts if there is a gap of more than 30 minutes between prompts.
#Sessionization
#Window Functions
#Time Series
Data Scientist
•
Coding
•
medium
Write a SQL query to calculate the week-over-week retention rate of users who interacted with a specific new model version.
#Cohort Analysis
#Retention
#Self Joins
Data Scientist
•
Coding
•
medium
How would you identify potential prompt injection attempts in our logs using a combination of regex and SQL?
#Regex
#Security
#Text Processing
Data Scientist
•
Coding
•
easy
Write a SQL query to calculate the 7-day rolling average of API requests per organization.
#Moving Averages
#Window Functions
Data Scientist
•
Coding
•
medium
Write a Python function to compute the BLEU score between a candidate string and a list of reference strings from scratch.
#NLP
#Algorithms
#String Manipulation
Data Scientist
•
Coding
•
medium
Implement an algorithm to perform stratified sampling on a large dataset of RLHF prompts, ensuring equal representation across 10 different safety categories.
#Sampling
#Data Manipulation
#Pandas
Data Scientist
•
Coding
•
hard
Write a Python function to find the longest repeating substring in a generated text. This is useful for detecting if a model has fallen into a repetitive loop.
#Dynamic Programming
#Suffix Trees
#String Algorithms
Data Scientist
•
Coding
•
easy
Given a massive JSONL file of model interaction logs, write a memory-efficient Python script to extract the error rate per model version.
#File I/O
#Memory Management
#JSON
Data Scientist
•
Coding
•
medium
Implement the TF-IDF algorithm from scratch in Python to find the most important keywords in a set of user queries.
#NLP
#Math
#Data Structures
Data Scientist
•
System Design
•
hard
Design a telemetry and data pipeline system to capture human-in-the-loop feedback (e.g., thumbs up/down, rewritten responses) for RLHF at scale.
#Data Pipelines
#RLHF
#Streaming Data
Data Scientist
•
System Design
•
hard
Design an automated evaluation pipeline (Auto-Eval) that uses a stronger model (e.g., Opus) to grade a weaker model's (e.g., Haiku) outputs. How do you detect and mitigate positional bias and verbosity bias in the evaluator?
#Auto-Evals
#LLM-as-a-Judge
#Bias Mitigation
Data Scientist
•
System Design
•
medium
Design a telemetry and metrics dashboard system to monitor Claude's real-time refusal rates across different API endpoints and customer tiers.
#Data Architecture
#Monitoring
#Streaming
Data Scientist
•
System Design
•
hard
How would you design a data pipeline to ingest, clean, and deduplicate 100TB of web-scraped text for LLM pre-training?
#Big Data
#Data Engineering
#Spark
Data Scientist
•
System Design
•
hard
Design an evaluation system to continuously benchmark Claude against competitor models (like GPT-4) using both automated metrics and human-in-the-loop.
#MLOps
#Evaluation
#Human-in-the-loop
Data Scientist
•
System Design
•
medium
Design a system to track and attribute compute costs (GPU hours) to specific research experiments, model runs, and individual data scientists.
#Data Modeling
#Cloud Infrastructure
#Analytics
Data Scientist
•
System Design
•
hard
Propose an architecture for storing and querying billions of vector embeddings to support internal retrieval-augmented generation (RAG) experiments.
#Vector Databases
#Search
#Scalability
Data Scientist
•
System Design
•
hard
Design an experiment to test whether adding a new principle to Claude's Constitutional AI prompt improves user satisfaction without increasing refusal rates on benign queries.
#A/B Testing
#Constitutional AI
#Metrics
Data Scientist
•
System Design
•
hard
Design a telemetry and analytics system to monitor Claude's response latency, token generation speed, and output quality in real-time.
#Data Pipelines
#Real-time Analytics
#Monitoring
Data Scientist
•
System Design
•
medium
Design a dashboard and the underlying metrics suite for a new Claude enterprise feature that allows companies to upload their own knowledge bases.
#Metrics Design
#RAG
#B2B Analytics
Data Scientist
•
System Design
•
hard
How would you design a data pipeline to continuously evaluate model drift and degradation over time?
#MLOps
#Model Drift
#Data Engineering
Data Scientist
•
System Design
•
medium
Design an anomaly detection system to identify sudden spikes in API token usage that could indicate a compromised key or a scraping attack.
#Anomaly Detection
#Security
#Time Series
Data Scientist
•
Technical
•
hard
How would you design a robust evaluation metric to measure hallucination rates in Claude's summarization tasks across different domains (e.g., legal, medical, casual)?
#LLM Evaluation
#Hallucination
#Metrics Design
Data Scientist
•
Technical
•
medium
We recently rolled out a new Constitutional AI principle that makes Claude more harmless, but initial A/B tests show a 5% drop in user retention. How do you analyze this trade-off and what is your recommendation?
#A/B Testing
#Trade-off Analysis
#Product Analytics
Data Scientist
•
Technical
•
hard
You notice that Claude 3 Opus performs better overall on a benchmark than Claude 3 Sonnet, but when you break the data down by language (English, Spanish, Mandarin), Sonnet outperforms Opus in every single category. Explain how this is statistically possible.
#Simpson's Paradox
#Data Analysis
#Confounding Variables
Data Scientist
•
Technical
•
hard
From a data distribution and statistical perspective, explain the differences between preparing preference data for Direct Preference Optimization (DPO) versus traditional RLHF (PPO).
#RLHF
#DPO
#Preference Data
Data Scientist
•
Technical
•
medium
How would you determine the required sample size for human annotators grading Claude's helpfulness to achieve statistical significance, given historically high variance in inter-rater reliability?
#Sample Size Calculation
#Inter-rater Reliability
#Hypothesis Testing
Data Scientist
•
Technical
•
hard
How do you detect and mitigate data contamination (test set leakage) in the massive pre-training corpus of a large language model to ensure our benchmark scores are valid?
#Data Contamination
#Test Leakage
#Pre-training Data
Data Scientist
•
Technical
•
hard
How would you design an A/B test to evaluate if a new RLHF reward model improves Claude's helpfulness without degrading its safety?
#Experimentation
#RLHF
#Trade-offs
Data Scientist
•
Technical
•
medium
We want to measure the hallucination rate of a new model version. How do you define the metric and design the evaluation pipeline?
#LLM Evaluation
#Metrics
#Data Pipelines
Data Scientist
•
Technical
•
medium
Explain how you would handle Simpson's Paradox if you noticed it while analyzing human feedback data across different demographic groups of annotators.
#Statistics
#Data Analysis
#Bias
Data Scientist
•
Technical
•
medium
How do you determine the required sample size for a human evaluation task where the baseline win rate is 52% and we want to detect a 1% absolute improvement with 95% confidence?
#A/B Testing
#Power Analysis
#Statistics
Data Scientist
•
Technical
•
easy
What statistical test would you use to compare the latency distributions of two different inference engine configurations, given that latency is heavily right-skewed?
#Hypothesis Testing
#Non-parametric Stats
Data Scientist
•
Technical
•
medium
If our automated safety classifier has a false positive rate of 5%, and 1% of all prompts are actually unsafe, what is the probability that a flagged prompt is actually unsafe?
#Bayes Theorem
#Probability
Data Scientist
•
Technical
•
hard
How would you model the relationship between model parameter count, training compute, and downstream zero-shot accuracy to predict the performance of our next-generation model?
#Scaling Laws
#Regression
#Predictive Modeling
Data Scientist
•
Technical
•
hard
Describe how you would detect data contamination (test set leakage) in a massive 5-trillion token pre-training corpus.
#Data Quality
#NLP
#Algorithms
Data Scientist
•
Technical
•
medium
Explain the concept of Constitutional AI. How would you quantitatively measure if a model is adhering to its constitution?
#Constitutional AI
#Alignment
#Metrics
Data Scientist
•
Technical
•
medium
What are the trade-offs between using automated LLM-as-a-judge evaluations versus human annotators for scoring model helpfulness?
#LLM Evaluation
#Bias
#Data Quality
Data Scientist
•
Technical
•
hard
How do you mitigate the 'length bias' (where models or humans prefer longer answers regardless of quality) in RLHF data?
#RLHF
#Bias Mitigation
#Modeling
Data Scientist
•
Technical
•
hard
Explain the difference between PPO (Proximal Policy Optimization) and DPO (Direct Preference Optimization) from a data requirements and modeling perspective.
#RLHF
#DPO
#PPO
Data Scientist
•
Technical
•
medium
How would you evaluate the coding capabilities of an LLM beyond just exact-match pass@k on standard datasets like HumanEval?
#Evaluation
#Code Generation
#Metrics
Data Scientist
•
Technical
•
hard
How would you design an evaluation metric to quantify the rate of subtle hallucinations in Claude's long-form summarization tasks?
#LLM Evaluation
#NLP
#Metrics Design
Data Scientist
•
Technical
•
medium
Given a dataset of human preference ratings for RLHF, how would you identify and correct for annotator bias or inconsistent grading?
#RLHF
#Data Quality
#Statistical Testing
Data Scientist
•
Technical
•
hard
How would you measure the trade-off between helpfulness and harmlessness (the 'HHH' alignment) when evaluating a new model checkpoint?
#AI Safety
#Trade-off Analysis
#Experimentation
Data Scientist
•
Technical
•
medium
How would you detect and quantify data contamination (test set leakage) in our pre-training corpus?
#Data Processing
#NLP
#Model Evaluation
Data Scientist
•
Technical
•
medium
If we want to detect a 0.1% increase in severe safety violations (a very rare event), how would you calculate the required sample size for the A/B test?
#A/B Testing
#Sample Size
#Rare Events
Data Scientist
•
Technical
•
medium
Describe a scenario where Simpson's Paradox might occur in our model evaluation data, and how you would resolve it.
#Data Analysis
#Causal Inference
#Probability
Data Scientist
•
Technical
•
hard
How would you use a Bayesian approach to establish an upper bound on the probability of Claude generating a harmful response, given zero observed failures in a sample of 10,000 prompts?
#Bayesian Statistics
#Risk Assessment
Data Scientist
•
Technical
•
medium
Formulate a composite metric to capture 'user frustration' during a multi-turn chat with Claude.
#User Behavior
#Metrics Design
#NLP
Data Scientist
•
Technical
•
hard
Explain the mathematics and intuition behind Proximal Policy Optimization (PPO) at a high level, and why it is preferred for RLHF.
#Reinforcement Learning
#Math
#RLHF
Data Scientist
•
Technical
•
medium
How do you handle severe class imbalance when training a classifier to detect rare jailbreak attempts in user prompts?
#Classification
#Imbalanced Data
#Security
Data Scientist
•
Technical
•
hard
What are the primary limitations and biases of using strong LLMs as judges for evaluating the outputs of other LLMs?
#LLM Evaluation
#Bias
#Research Methodology
Data Scientist
•
Technical
•
medium
Explain how you would cluster millions of unstructured user prompts to identify emerging use cases and feature requests.
#Unsupervised Learning
#NLP
#Clustering
Data Scientist
•
Technical
•
hard
How would you estimate the causal impact of a new Constitutional AI principle on long-term user retention, given that we cannot run a perfectly randomized control trial for months?
#Causal Inference
#Observational Data
#Retention
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